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MIPS: Fix LLVM build issue.
[linux-2.6-block.git] / fs / dlm / lock.c
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e7fd4179
DT		 1/******************************************************************************
2*******************************************************************************
3**
7fe2b319 4** Copyright (C) 2005-2010 Red Hat, Inc. All rights reserved.
e7fd4179
DT		 5**
6** This copyrighted material is made available to anyone wishing to use,
7** modify, copy, or redistribute it subject to the terms and conditions
8** of the GNU General Public License v.2.
9**
10*******************************************************************************
11******************************************************************************/
12
13/* Central locking logic has four stages:
14
15 dlm_lock()
16 dlm_unlock()
17
18 request_lock(ls, lkb)
19 convert_lock(ls, lkb)
20 unlock_lock(ls, lkb)
21 cancel_lock(ls, lkb)
22
23 _request_lock(r, lkb)
24 _convert_lock(r, lkb)
25 _unlock_lock(r, lkb)
26 _cancel_lock(r, lkb)
27
28 do_request(r, lkb)
29 do_convert(r, lkb)
30 do_unlock(r, lkb)
31 do_cancel(r, lkb)
32
33 Stage 1 (lock, unlock) is mainly about checking input args and
34 splitting into one of the four main operations:
35
36 dlm_lock = request_lock
37 dlm_lock+CONVERT = convert_lock
38 dlm_unlock = unlock_lock
39 dlm_unlock+CANCEL = cancel_lock
40
41 Stage 2, xxxx_lock(), just finds and locks the relevant rsb which is
42 provided to the next stage.
43
44 Stage 3, _xxxx_lock(), determines if the operation is local or remote.
45 When remote, it calls send_xxxx(), when local it calls do_xxxx().
46
47 Stage 4, do_xxxx(), is the guts of the operation. It manipulates the
48 given rsb and lkb and queues callbacks.
49
50 For remote operations, send_xxxx() results in the corresponding do_xxxx()
51 function being executed on the remote node. The connecting send/receive
52 calls on local (L) and remote (R) nodes:
53
54 L: send_xxxx() -> R: receive_xxxx()
55 R: do_xxxx()
56 L: receive_xxxx_reply() <- R: send_xxxx_reply()
57*/
597d0cae 58#include <linux/types.h>
9beb3bf5 59#include <linux/rbtree.h>
5a0e3ad6 60#include <linux/slab.h>
e7fd4179 61#include "dlm_internal.h"
597d0cae 62#include <linux/dlm_device.h>
e7fd4179
DT		 63#include "memory.h"
64#include "lowcomms.h"
65#include "requestqueue.h"
66#include "util.h"
67#include "dir.h"
68#include "member.h"
69#include "lockspace.h"
70#include "ast.h"
71#include "lock.h"
72#include "rcom.h"
73#include "recover.h"
74#include "lvb_table.h"
597d0cae 75#include "user.h"
e7fd4179
DT		 76#include "config.h"
77
78static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb);
79static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb);
80static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb);
81static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb);
82static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb);
83static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode);
84static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb);
85static int send_remove(struct dlm_rsb *r);
86static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
3ae1acf9 87static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb);
e7fd4179
DT		 88static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
89 struct dlm_message *ms);
90static int receive_extralen(struct dlm_message *ms);
8499137d 91static void do_purge(struct dlm_ls *ls, int nodeid, int pid);
3ae1acf9 92static void del_timeout(struct dlm_lkb *lkb);
c04fecb4 93static void toss_rsb(struct kref *kref);
e7fd4179
DT		 94
95/*
96 * Lock compatibilty matrix - thanks Steve
97 * UN = Unlocked state. Not really a state, used as a flag
98 * PD = Padding. Used to make the matrix a nice power of two in size
99 * Other states are the same as the VMS DLM.
100 * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same)
101 */
102
103static const int __dlm_compat_matrix[8][8] = {
104 /* UN NL CR CW PR PW EX PD */
105 {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */
106 {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */
107 {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */
108 {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */
109 {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */
110 {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */
111 {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */
112 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
113};
114
115/*
116 * This defines the direction of transfer of LVB data.
117 * Granted mode is the row; requested mode is the column.
118 * Usage: matrix[grmode+1][rqmode+1]
119 * 1 = LVB is returned to the caller
120 * 0 = LVB is written to the resource
121 * -1 = nothing happens to the LVB
122 */
123
124const int dlm_lvb_operations[8][8] = {
125 /* UN NL CR CW PR PW EX PD*/
126 { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */
127 { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */
128 { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */
129 { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */
130 { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */
131 { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */
132 { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */
133 { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */
134};
e7fd4179
DT		 135
136#define modes_compat(gr, rq) \
137 __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1]
138
139int dlm_modes_compat(int mode1, int mode2)
140{
141 return __dlm_compat_matrix[mode1 + 1][mode2 + 1];
142}
143
144/*
145 * Compatibility matrix for conversions with QUECVT set.
146 * Granted mode is the row; requested mode is the column.
147 * Usage: matrix[grmode+1][rqmode+1]
148 */
149
150static const int __quecvt_compat_matrix[8][8] = {
151 /* UN NL CR CW PR PW EX PD */
152 {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */
153 {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */
154 {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */
155 {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */
156 {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */
157 {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */
158 {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */
159 {0, 0, 0, 0, 0, 0, 0, 0} /* PD */
160};
161
597d0cae 162void dlm_print_lkb(struct dlm_lkb *lkb)
e7fd4179 163{
6d40c4a7 164 printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x "
4875647a 165 "sts %d rq %d gr %d wait_type %d wait_nodeid %d seq %llu\n",
e7fd4179
DT		 166 lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags,
167 lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode,
4875647a
DT		 168 lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_wait_nodeid,
169 (unsigned long long)lkb->lkb_recover_seq);
e7fd4179
DT		 170}
171
170e19ab 172static void dlm_print_rsb(struct dlm_rsb *r)
e7fd4179 173{
c04fecb4
DT		 174 printk(KERN_ERR "rsb: nodeid %d master %d dir %d flags %lx first %x "
175 "rlc %d name %s\n",
176 r->res_nodeid, r->res_master_nodeid, r->res_dir_nodeid,
177 r->res_flags, r->res_first_lkid, r->res_recover_locks_count,
178 r->res_name);
e7fd4179
DT		 179}
180
a345da3e
DT		 181void dlm_dump_rsb(struct dlm_rsb *r)
182{
183 struct dlm_lkb *lkb;
184
185 dlm_print_rsb(r);
186
187 printk(KERN_ERR "rsb: root_list empty %d recover_list empty %d\n",
188 list_empty(&r->res_root_list), list_empty(&r->res_recover_list));
189 printk(KERN_ERR "rsb lookup list\n");
190 list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup)
191 dlm_print_lkb(lkb);
192 printk(KERN_ERR "rsb grant queue:\n");
193 list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue)
194 dlm_print_lkb(lkb);
195 printk(KERN_ERR "rsb convert queue:\n");
196 list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue)
197 dlm_print_lkb(lkb);
198 printk(KERN_ERR "rsb wait queue:\n");
199 list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue)
200 dlm_print_lkb(lkb);
201}
202
e7fd4179
DT		 203/* Threads cannot use the lockspace while it's being recovered */
204
85e86edf 205static inline void dlm_lock_recovery(struct dlm_ls *ls)
e7fd4179
DT		 206{
207 down_read(&ls->ls_in_recovery);
208}
209
85e86edf 210void dlm_unlock_recovery(struct dlm_ls *ls)
e7fd4179
DT		 211{
212 up_read(&ls->ls_in_recovery);
213}
214
85e86edf 215int dlm_lock_recovery_try(struct dlm_ls *ls)
e7fd4179
DT		 216{
217 return down_read_trylock(&ls->ls_in_recovery);
218}
219
220static inline int can_be_queued(struct dlm_lkb *lkb)
221{
222 return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE);
223}
224
225static inline int force_blocking_asts(struct dlm_lkb *lkb)
226{
227 return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST);
228}
229
230static inline int is_demoted(struct dlm_lkb *lkb)
231{
232 return (lkb->lkb_sbflags & DLM_SBF_DEMOTED);
233}
234
7d3c1feb
DT		 235static inline int is_altmode(struct dlm_lkb *lkb)
236{
237 return (lkb->lkb_sbflags & DLM_SBF_ALTMODE);
238}
239
240static inline int is_granted(struct dlm_lkb *lkb)
241{
242 return (lkb->lkb_status == DLM_LKSTS_GRANTED);
243}
244
e7fd4179
DT		 245static inline int is_remote(struct dlm_rsb *r)
246{
247 DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r););
248 return !!r->res_nodeid;
249}
250
251static inline int is_process_copy(struct dlm_lkb *lkb)
252{
253 return (lkb->lkb_nodeid && !(lkb->lkb_flags & DLM_IFL_MSTCPY));
254}
255
256static inline int is_master_copy(struct dlm_lkb *lkb)
257{
90135925 258 return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? 1 : 0;
e7fd4179
DT		 259}
260
261static inline int middle_conversion(struct dlm_lkb *lkb)
262{
263 if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) ||
264 (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW))
90135925
DT		 265 return 1;
266 return 0;
e7fd4179
DT		 267}
268
269static inline int down_conversion(struct dlm_lkb *lkb)
270{
271 return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode);
272}
273
ef0c2bb0
DT		 274static inline int is_overlap_unlock(struct dlm_lkb *lkb)
275{
276 return lkb->lkb_flags & DLM_IFL_OVERLAP_UNLOCK;
277}
278
279static inline int is_overlap_cancel(struct dlm_lkb *lkb)
280{
281 return lkb->lkb_flags & DLM_IFL_OVERLAP_CANCEL;
282}
283
284static inline int is_overlap(struct dlm_lkb *lkb)
285{
286 return (lkb->lkb_flags & (DLM_IFL_OVERLAP_UNLOCK |
287 DLM_IFL_OVERLAP_CANCEL));
288}
289
e7fd4179
DT		 290static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
291{
292 if (is_master_copy(lkb))
293 return;
294
3ae1acf9
DT		 295 del_timeout(lkb);
296
e7fd4179
DT		 297 DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb););
298
3ae1acf9
DT		 299 /* if the operation was a cancel, then return -DLM_ECANCEL, if a
300 timeout caused the cancel then return -ETIMEDOUT */
301 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_TIMEOUT_CANCEL)) {
302 lkb->lkb_flags &= ~DLM_IFL_TIMEOUT_CANCEL;
303 rv = -ETIMEDOUT;
304 }
305
8b4021fa
DT		 306 if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_DEADLOCK_CANCEL)) {
307 lkb->lkb_flags &= ~DLM_IFL_DEADLOCK_CANCEL;
308 rv = -EDEADLK;
309 }
310
23e8e1aa 311 dlm_add_cb(lkb, DLM_CB_CAST, lkb->lkb_grmode, rv, lkb->lkb_sbflags);
e7fd4179
DT		 312}
313
ef0c2bb0
DT		 314static inline void queue_cast_overlap(struct dlm_rsb *r, struct dlm_lkb *lkb)
315{
316 queue_cast(r, lkb,
317 is_overlap_unlock(lkb) ? -DLM_EUNLOCK : -DLM_ECANCEL);
318}
319
e7fd4179
DT		 320static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode)
321{
b6fa8796 322 if (is_master_copy(lkb)) {
e7fd4179 323 send_bast(r, lkb, rqmode);
b6fa8796 324 } else {
23e8e1aa 325 dlm_add_cb(lkb, DLM_CB_BAST, rqmode, 0, 0);
b6fa8796 326 }
e7fd4179
DT		 327}
328
329/*
330 * Basic operations on rsb's and lkb's
331 */
332
c04fecb4
DT		 333/* This is only called to add a reference when the code already holds
334 a valid reference to the rsb, so there's no need for locking. */
335
336static inline void hold_rsb(struct dlm_rsb *r)
337{
338 kref_get(&r->res_ref);
339}
340
341void dlm_hold_rsb(struct dlm_rsb *r)
342{
343 hold_rsb(r);
344}
345
346/* When all references to the rsb are gone it's transferred to
347 the tossed list for later disposal. */
348
349static void put_rsb(struct dlm_rsb *r)
350{
351 struct dlm_ls *ls = r->res_ls;
352 uint32_t bucket = r->res_bucket;
353
354 spin_lock(&ls->ls_rsbtbl[bucket].lock);
355 kref_put(&r->res_ref, toss_rsb);
356 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
357}
358
359void dlm_put_rsb(struct dlm_rsb *r)
360{
361 put_rsb(r);
362}
363
3881ac04
DT		 364static int pre_rsb_struct(struct dlm_ls *ls)
365{
366 struct dlm_rsb *r1, *r2;
367 int count = 0;
368
369 spin_lock(&ls->ls_new_rsb_spin);
370 if (ls->ls_new_rsb_count > dlm_config.ci_new_rsb_count / 2) {
371 spin_unlock(&ls->ls_new_rsb_spin);
372 return 0;
373 }
374 spin_unlock(&ls->ls_new_rsb_spin);
375
376 r1 = dlm_allocate_rsb(ls);
377 r2 = dlm_allocate_rsb(ls);
378
379 spin_lock(&ls->ls_new_rsb_spin);
380 if (r1) {
381 list_add(&r1->res_hashchain, &ls->ls_new_rsb);
382 ls->ls_new_rsb_count++;
383 }
384 if (r2) {
385 list_add(&r2->res_hashchain, &ls->ls_new_rsb);
386 ls->ls_new_rsb_count++;
387 }
388 count = ls->ls_new_rsb_count;
389 spin_unlock(&ls->ls_new_rsb_spin);
390
391 if (!count)
392 return -ENOMEM;
393 return 0;
394}
395
396/* If ls->ls_new_rsb is empty, return -EAGAIN, so the caller can
397 unlock any spinlocks, go back and call pre_rsb_struct again.
398 Otherwise, take an rsb off the list and return it. */
399
400static int get_rsb_struct(struct dlm_ls *ls, char *name, int len,
401 struct dlm_rsb **r_ret)
e7fd4179
DT		 402{
403 struct dlm_rsb *r;
3881ac04
DT		 404 int count;
405
406 spin_lock(&ls->ls_new_rsb_spin);
407 if (list_empty(&ls->ls_new_rsb)) {
408 count = ls->ls_new_rsb_count;
409 spin_unlock(&ls->ls_new_rsb_spin);
410 log_debug(ls, "find_rsb retry %d %d %s",
411 count, dlm_config.ci_new_rsb_count, name);
412 return -EAGAIN;
413 }
e7fd4179 414
3881ac04
DT		 415 r = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb, res_hashchain);
416 list_del(&r->res_hashchain);
9beb3bf5
BP		 417 /* Convert the empty list_head to a NULL rb_node for tree usage: */
418 memset(&r->res_hashnode, 0, sizeof(struct rb_node));
3881ac04
DT		 419 ls->ls_new_rsb_count--;
420 spin_unlock(&ls->ls_new_rsb_spin);
e7fd4179
DT		 421
422 r->res_ls = ls;
423 r->res_length = len;
424 memcpy(r->res_name, name, len);
90135925 425 mutex_init(&r->res_mutex);
e7fd4179
DT		 426
427 INIT_LIST_HEAD(&r->res_lookup);
428 INIT_LIST_HEAD(&r->res_grantqueue);
429 INIT_LIST_HEAD(&r->res_convertqueue);
430 INIT_LIST_HEAD(&r->res_waitqueue);
431 INIT_LIST_HEAD(&r->res_root_list);
432 INIT_LIST_HEAD(&r->res_recover_list);
433
3881ac04
DT		 434 *r_ret = r;
435 return 0;
e7fd4179
DT		 436}
437
9beb3bf5
BP		 438static int rsb_cmp(struct dlm_rsb *r, const char *name, int nlen)
439{
440 char maxname[DLM_RESNAME_MAXLEN];
441
442 memset(maxname, 0, DLM_RESNAME_MAXLEN);
443 memcpy(maxname, name, nlen);
444 return memcmp(r->res_name, maxname, DLM_RESNAME_MAXLEN);
445}
446
7210cb7a 447int dlm_search_rsb_tree(struct rb_root *tree, char *name, int len,
c04fecb4 448 struct dlm_rsb **r_ret)
e7fd4179 449{
9beb3bf5 450 struct rb_node *node = tree->rb_node;
e7fd4179 451 struct dlm_rsb *r;
9beb3bf5
BP		 452 int rc;
453
454 while (node) {
455 r = rb_entry(node, struct dlm_rsb, res_hashnode);
456 rc = rsb_cmp(r, name, len);
457 if (rc < 0)
458 node = node->rb_left;
459 else if (rc > 0)
460 node = node->rb_right;
461 else
e7fd4179
DT		 462 goto found;
463 }
18c60c0a 464 *r_ret = NULL;
597d0cae 465 return -EBADR;
e7fd4179
DT		 466
467 found:
e7fd4179 468 *r_ret = r;
c04fecb4 469 return 0;
e7fd4179
DT		 470}
471
9beb3bf5
BP		 472static int rsb_insert(struct dlm_rsb *rsb, struct rb_root *tree)
473{
474 struct rb_node **newn = &tree->rb_node;
475 struct rb_node *parent = NULL;
476 int rc;
477
478 while (*newn) {
479 struct dlm_rsb *cur = rb_entry(*newn, struct dlm_rsb,
480 res_hashnode);
481
482 parent = *newn;
483 rc = rsb_cmp(cur, rsb->res_name, rsb->res_length);
484 if (rc < 0)
485 newn = &parent->rb_left;
486 else if (rc > 0)
487 newn = &parent->rb_right;
488 else {
489 log_print("rsb_insert match");
490 dlm_dump_rsb(rsb);
491 dlm_dump_rsb(cur);
492 return -EEXIST;
493 }
494 }
495
496 rb_link_node(&rsb->res_hashnode, parent, newn);
497 rb_insert_color(&rsb->res_hashnode, tree);
498 return 0;
499}
500
c04fecb4
DT		 501/*
502 * Find rsb in rsbtbl and potentially create/add one
503 *
504 * Delaying the release of rsb's has a similar benefit to applications keeping
505 * NL locks on an rsb, but without the guarantee that the cached master value
506 * will still be valid when the rsb is reused. Apps aren't always smart enough
507 * to keep NL locks on an rsb that they may lock again shortly; this can lead
508 * to excessive master lookups and removals if we don't delay the release.
509 *
510 * Searching for an rsb means looking through both the normal list and toss
511 * list. When found on the toss list the rsb is moved to the normal list with
512 * ref count of 1; when found on normal list the ref count is incremented.
513 *
514 * rsb's on the keep list are being used locally and refcounted.
515 * rsb's on the toss list are not being used locally, and are not refcounted.
516 *
517 * The toss list rsb's were either
518 * - previously used locally but not any more (were on keep list, then
519 * moved to toss list when last refcount dropped)
520 * - created and put on toss list as a directory record for a lookup
521 * (we are the dir node for the res, but are not using the res right now,
522 * but some other node is)
523 *
524 * The purpose of find_rsb() is to return a refcounted rsb for local use.
525 * So, if the given rsb is on the toss list, it is moved to the keep list
526 * before being returned.
527 *
528 * toss_rsb() happens when all local usage of the rsb is done, i.e. no
529 * more refcounts exist, so the rsb is moved from the keep list to the
530 * toss list.
531 *
532 * rsb's on both keep and toss lists are used for doing a name to master
533 * lookups. rsb's that are in use locally (and being refcounted) are on
534 * the keep list, rsb's that are not in use locally (not refcounted) and
535 * only exist for name/master lookups are on the toss list.
536 *
537 * rsb's on the toss list who's dir_nodeid is not local can have stale
538 * name/master mappings. So, remote requests on such rsb's can potentially
539 * return with an error, which means the mapping is stale and needs to
540 * be updated with a new lookup. (The idea behind MASTER UNCERTAIN and
541 * first_lkid is to keep only a single outstanding request on an rsb
542 * while that rsb has a potentially stale master.)
543 */
544
545static int find_rsb_dir(struct dlm_ls *ls, char *name, int len,
546 uint32_t hash, uint32_t b,
547 int dir_nodeid, int from_nodeid,
548 unsigned int flags, struct dlm_rsb **r_ret)
e7fd4179 549{
c04fecb4
DT		 550 struct dlm_rsb *r = NULL;
551 int our_nodeid = dlm_our_nodeid();
552 int from_local = 0;
553 int from_other = 0;
554 int from_dir = 0;
555 int create = 0;
e7fd4179
DT		 556 int error;
557
c04fecb4
DT		 558 if (flags & R_RECEIVE_REQUEST) {
559 if (from_nodeid == dir_nodeid)
560 from_dir = 1;
561 else
562 from_other = 1;
563 } else if (flags & R_REQUEST) {
564 from_local = 1;
565 }
566
567 /*
568 * flags & R_RECEIVE_RECOVER is from dlm_recover_master_copy, so
569 * from_nodeid has sent us a lock in dlm_recover_locks, believing
570 * we're the new master. Our local recovery may not have set
571 * res_master_nodeid to our_nodeid yet, so allow either. Don't
572 * create the rsb; dlm_recover_process_copy() will handle EBADR
573 * by resending.
574 *
575 * If someone sends us a request, we are the dir node, and we do
576 * not find the rsb anywhere, then recreate it. This happens if
577 * someone sends us a request after we have removed/freed an rsb
578 * from our toss list. (They sent a request instead of lookup
579 * because they are using an rsb from their toss list.)
580 */
581
582 if (from_local || from_dir ||
583 (from_other && (dir_nodeid == our_nodeid))) {
584 create = 1;
e7fd4179 585 }
57638bf3 586
c04fecb4
DT		 587 retry:
588 if (create) {
589 error = pre_rsb_struct(ls);
590 if (error < 0)
591 goto out;
592 }
593
594 spin_lock(&ls->ls_rsbtbl[b].lock);
595
596 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
e7fd4179 597 if (error)
c04fecb4
DT		 598 goto do_toss;
599
600 /*
601 * rsb is active, so we can't check master_nodeid without lock_rsb.
602 */
e7fd4179 603
c04fecb4
DT		 604 kref_get(&r->res_ref);
605 error = 0;
606 goto out_unlock;
607
608
609 do_toss:
610 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
9beb3bf5 611 if (error)
c04fecb4 612 goto do_new;
e7fd4179 613
c04fecb4
DT		 614 /*
615 * rsb found inactive (master_nodeid may be out of date unless
616 * we are the dir_nodeid or were the master) No other thread
617 * is using this rsb because it's on the toss list, so we can
618 * look at or update res_master_nodeid without lock_rsb.
619 */
e7fd4179 620
c04fecb4
DT		 621 if ((r->res_master_nodeid != our_nodeid) && from_other) {
622 /* our rsb was not master, and another node (not the dir node)
623 has sent us a request */
624 log_debug(ls, "find_rsb toss from_other %d master %d dir %d %s",
625 from_nodeid, r->res_master_nodeid, dir_nodeid,
626 r->res_name);
627 error = -ENOTBLK;
628 goto out_unlock;
629 }
630
631 if ((r->res_master_nodeid != our_nodeid) && from_dir) {
632 /* don't think this should ever happen */
633 log_error(ls, "find_rsb toss from_dir %d master %d",
634 from_nodeid, r->res_master_nodeid);
635 dlm_print_rsb(r);
636 /* fix it and go on */
637 r->res_master_nodeid = our_nodeid;
638 r->res_nodeid = 0;
e7fd4179
DT		 639 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
640 r->res_first_lkid = 0;
c04fecb4
DT		 641 }
642
643 if (from_local && (r->res_master_nodeid != our_nodeid)) {
644 /* Because we have held no locks on this rsb,
645 res_master_nodeid could have become stale. */
e7fd4179
DT		 646 rsb_set_flag(r, RSB_MASTER_UNCERTAIN);
647 r->res_first_lkid = 0;
c04fecb4
DT		 648 }
649
650 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
651 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
652 goto out_unlock;
653
654
655 do_new:
656 /*
657 * rsb not found
658 */
659
660 if (error == -EBADR && !create)
661 goto out_unlock;
662
663 error = get_rsb_struct(ls, name, len, &r);
664 if (error == -EAGAIN) {
665 spin_unlock(&ls->ls_rsbtbl[b].lock);
666 goto retry;
667 }
668 if (error)
669 goto out_unlock;
670
671 r->res_hash = hash;
672 r->res_bucket = b;
673 r->res_dir_nodeid = dir_nodeid;
674 kref_init(&r->res_ref);
675
676 if (from_dir) {
677 /* want to see how often this happens */
678 log_debug(ls, "find_rsb new from_dir %d recreate %s",
679 from_nodeid, r->res_name);
680 r->res_master_nodeid = our_nodeid;
681 r->res_nodeid = 0;
682 goto out_add;
683 }
684
685 if (from_other && (dir_nodeid != our_nodeid)) {
686 /* should never happen */
687 log_error(ls, "find_rsb new from_other %d dir %d our %d %s",
688 from_nodeid, dir_nodeid, our_nodeid, r->res_name);
689 dlm_free_rsb(r);
e8243f32 690 r = NULL;
c04fecb4
DT		 691 error = -ENOTBLK;
692 goto out_unlock;
693 }
694
695 if (from_other) {
696 log_debug(ls, "find_rsb new from_other %d dir %d %s",
697 from_nodeid, dir_nodeid, r->res_name);
698 }
699
700 if (dir_nodeid == our_nodeid) {
701 /* When we are the dir nodeid, we can set the master
702 node immediately */
703 r->res_master_nodeid = our_nodeid;
704 r->res_nodeid = 0;
e7fd4179 705 } else {
c04fecb4
DT		 706 /* set_master will send_lookup to dir_nodeid */
707 r->res_master_nodeid = 0;
708 r->res_nodeid = -1;
709 }
710
711 out_add:
712 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
713 out_unlock:
714 spin_unlock(&ls->ls_rsbtbl[b].lock);
715 out:
716 *r_ret = r;
717 return error;
718}
719
720/* During recovery, other nodes can send us new MSTCPY locks (from
721 dlm_recover_locks) before we've made ourself master (in
722 dlm_recover_masters). */
723
724static int find_rsb_nodir(struct dlm_ls *ls, char *name, int len,
725 uint32_t hash, uint32_t b,
726 int dir_nodeid, int from_nodeid,
727 unsigned int flags, struct dlm_rsb **r_ret)
728{
729 struct dlm_rsb *r = NULL;
730 int our_nodeid = dlm_our_nodeid();
731 int recover = (flags & R_RECEIVE_RECOVER);
732 int error;
733
734 retry:
735 error = pre_rsb_struct(ls);
736 if (error < 0)
737 goto out;
738
739 spin_lock(&ls->ls_rsbtbl[b].lock);
740
741 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
742 if (error)
743 goto do_toss;
744
745 /*
746 * rsb is active, so we can't check master_nodeid without lock_rsb.
747 */
748
749 kref_get(&r->res_ref);
750 goto out_unlock;
751
752
753 do_toss:
754 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
755 if (error)
756 goto do_new;
757
758 /*
759 * rsb found inactive. No other thread is using this rsb because
760 * it's on the toss list, so we can look at or update
761 * res_master_nodeid without lock_rsb.
762 */
763
764 if (!recover && (r->res_master_nodeid != our_nodeid) && from_nodeid) {
765 /* our rsb is not master, and another node has sent us a
766 request; this should never happen */
767 log_error(ls, "find_rsb toss from_nodeid %d master %d dir %d",
768 from_nodeid, r->res_master_nodeid, dir_nodeid);
769 dlm_print_rsb(r);
770 error = -ENOTBLK;
771 goto out_unlock;
e7fd4179 772 }
c04fecb4
DT		 773
774 if (!recover && (r->res_master_nodeid != our_nodeid) &&
775 (dir_nodeid == our_nodeid)) {
776 /* our rsb is not master, and we are dir; may as well fix it;
777 this should never happen */
778 log_error(ls, "find_rsb toss our %d master %d dir %d",
779 our_nodeid, r->res_master_nodeid, dir_nodeid);
780 dlm_print_rsb(r);
781 r->res_master_nodeid = our_nodeid;
782 r->res_nodeid = 0;
783 }
784
785 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
786 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
787 goto out_unlock;
788
789
790 do_new:
791 /*
792 * rsb not found
793 */
794
795 error = get_rsb_struct(ls, name, len, &r);
796 if (error == -EAGAIN) {
797 spin_unlock(&ls->ls_rsbtbl[b].lock);
798 goto retry;
799 }
800 if (error)
801 goto out_unlock;
802
803 r->res_hash = hash;
804 r->res_bucket = b;
805 r->res_dir_nodeid = dir_nodeid;
806 r->res_master_nodeid = dir_nodeid;
807 r->res_nodeid = (dir_nodeid == our_nodeid) ? 0 : dir_nodeid;
808 kref_init(&r->res_ref);
809
810 error = rsb_insert(r, &ls->ls_rsbtbl[b].keep);
811 out_unlock:
812 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 813 out:
814 *r_ret = r;
815 return error;
816}
817
c04fecb4
DT		 818static int find_rsb(struct dlm_ls *ls, char *name, int len, int from_nodeid,
819 unsigned int flags, struct dlm_rsb **r_ret)
820{
821 uint32_t hash, b;
822 int dir_nodeid;
823
824 if (len > DLM_RESNAME_MAXLEN)
825 return -EINVAL;
826
827 hash = jhash(name, len, 0);
828 b = hash & (ls->ls_rsbtbl_size - 1);
829
830 dir_nodeid = dlm_hash2nodeid(ls, hash);
831
832 if (dlm_no_directory(ls))
833 return find_rsb_nodir(ls, name, len, hash, b, dir_nodeid,
834 from_nodeid, flags, r_ret);
835 else
836 return find_rsb_dir(ls, name, len, hash, b, dir_nodeid,
837 from_nodeid, flags, r_ret);
838}
839
840/* we have received a request and found that res_master_nodeid != our_nodeid,
841 so we need to return an error or make ourself the master */
842
843static int validate_master_nodeid(struct dlm_ls *ls, struct dlm_rsb *r,
844 int from_nodeid)
845{
846 if (dlm_no_directory(ls)) {
847 log_error(ls, "find_rsb keep from_nodeid %d master %d dir %d",
848 from_nodeid, r->res_master_nodeid,
849 r->res_dir_nodeid);
850 dlm_print_rsb(r);
851 return -ENOTBLK;
852 }
853
854 if (from_nodeid != r->res_dir_nodeid) {
855 /* our rsb is not master, and another node (not the dir node)
856 has sent us a request. this is much more common when our
857 master_nodeid is zero, so limit debug to non-zero. */
858
859 if (r->res_master_nodeid) {
860 log_debug(ls, "validate master from_other %d master %d "
861 "dir %d first %x %s", from_nodeid,
862 r->res_master_nodeid, r->res_dir_nodeid,
863 r->res_first_lkid, r->res_name);
864 }
865 return -ENOTBLK;
866 } else {
867 /* our rsb is not master, but the dir nodeid has sent us a
868 request; this could happen with master 0 / res_nodeid -1 */
869
870 if (r->res_master_nodeid) {
871 log_error(ls, "validate master from_dir %d master %d "
872 "first %x %s",
873 from_nodeid, r->res_master_nodeid,
874 r->res_first_lkid, r->res_name);
875 }
876
877 r->res_master_nodeid = dlm_our_nodeid();
878 r->res_nodeid = 0;
879 return 0;
880 }
881}
882
e7fd4179 883/*
c04fecb4
DT		 884 * We're the dir node for this res and another node wants to know the
885 * master nodeid. During normal operation (non recovery) this is only
886 * called from receive_lookup(); master lookups when the local node is
887 * the dir node are done by find_rsb().
e7fd4179 888 *
c04fecb4
DT		 889 * normal operation, we are the dir node for a resource
890 * . _request_lock
891 * . set_master
892 * . send_lookup
893 * . receive_lookup
894 * . dlm_master_lookup flags 0
e7fd4179 895 *
c04fecb4
DT		 896 * recover directory, we are rebuilding dir for all resources
897 * . dlm_recover_directory
898 * . dlm_rcom_names
899 * remote node sends back the rsb names it is master of and we are dir of
900 * . dlm_master_lookup RECOVER_DIR (fix_master 0, from_master 1)
901 * we either create new rsb setting remote node as master, or find existing
902 * rsb and set master to be the remote node.
903 *
904 * recover masters, we are finding the new master for resources
905 * . dlm_recover_masters
906 * . recover_master
907 * . dlm_send_rcom_lookup
908 * . receive_rcom_lookup
909 * . dlm_master_lookup RECOVER_MASTER (fix_master 1, from_master 0)
e7fd4179
DT		 910 */
911
c04fecb4
DT		 912int dlm_master_lookup(struct dlm_ls *ls, int from_nodeid, char *name, int len,
913 unsigned int flags, int *r_nodeid, int *result)
e7fd4179 914{
3881ac04 915 struct dlm_rsb *r = NULL;
c04fecb4
DT		 916 uint32_t hash, b;
917 int from_master = (flags & DLM_LU_RECOVER_DIR);
918 int fix_master = (flags & DLM_LU_RECOVER_MASTER);
919 int our_nodeid = dlm_our_nodeid();
920 int dir_nodeid, error, toss_list = 0;
ef58bcca 921
c04fecb4
DT		 922 if (len > DLM_RESNAME_MAXLEN)
923 return -EINVAL;
924
925 if (from_nodeid == our_nodeid) {
926 log_error(ls, "dlm_master_lookup from our_nodeid %d flags %x",
927 our_nodeid, flags);
928 return -EINVAL;
3881ac04 929 }
e7fd4179 930
c04fecb4
DT		 931 hash = jhash(name, len, 0);
932 b = hash & (ls->ls_rsbtbl_size - 1);
e7fd4179 933
c04fecb4
DT		 934 dir_nodeid = dlm_hash2nodeid(ls, hash);
935 if (dir_nodeid != our_nodeid) {
936 log_error(ls, "dlm_master_lookup from %d dir %d our %d h %x %d",
937 from_nodeid, dir_nodeid, our_nodeid, hash,
938 ls->ls_num_nodes);
939 *r_nodeid = -1;
940 return -EINVAL;
941 }
e7fd4179 942
3881ac04 943 retry:
c04fecb4
DT		 944 error = pre_rsb_struct(ls);
945 if (error < 0)
946 return error;
947
948 spin_lock(&ls->ls_rsbtbl[b].lock);
949 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
950 if (!error) {
951 /* because the rsb is active, we need to lock_rsb before
952 checking/changing re_master_nodeid */
953
954 hold_rsb(r);
955 spin_unlock(&ls->ls_rsbtbl[b].lock);
956 lock_rsb(r);
957 goto found;
3881ac04
DT		 958 }
959
c04fecb4
DT		 960 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
961 if (error)
962 goto not_found;
3881ac04 963
c04fecb4
DT		 964 /* because the rsb is inactive (on toss list), it's not refcounted
965 and lock_rsb is not used, but is protected by the rsbtbl lock */
e7fd4179 966
c04fecb4
DT		 967 toss_list = 1;
968 found:
969 if (r->res_dir_nodeid != our_nodeid) {
970 /* should not happen, but may as well fix it and carry on */
971 log_error(ls, "dlm_master_lookup res_dir %d our %d %s",
972 r->res_dir_nodeid, our_nodeid, r->res_name);
973 r->res_dir_nodeid = our_nodeid;
974 }
975
976 if (fix_master && dlm_is_removed(ls, r->res_master_nodeid)) {
977 /* Recovery uses this function to set a new master when
978 the previous master failed. Setting NEW_MASTER will
979 force dlm_recover_masters to call recover_master on this
980 rsb even though the res_nodeid is no longer removed. */
981
982 r->res_master_nodeid = from_nodeid;
983 r->res_nodeid = from_nodeid;
984 rsb_set_flag(r, RSB_NEW_MASTER);
985
986 if (toss_list) {
987 /* I don't think we should ever find it on toss list. */
988 log_error(ls, "dlm_master_lookup fix_master on toss");
989 dlm_dump_rsb(r);
990 }
991 }
e7fd4179 992
c04fecb4
DT		 993 if (from_master && (r->res_master_nodeid != from_nodeid)) {
994 /* this will happen if from_nodeid became master during
995 a previous recovery cycle, and we aborted the previous
996 cycle before recovering this master value */
997
998 log_limit(ls, "dlm_master_lookup from_master %d "
999 "master_nodeid %d res_nodeid %d first %x %s",
1000 from_nodeid, r->res_master_nodeid, r->res_nodeid,
1001 r->res_first_lkid, r->res_name);
1002
1003 if (r->res_master_nodeid == our_nodeid) {
1004 log_error(ls, "from_master %d our_master", from_nodeid);
1005 dlm_dump_rsb(r);
1006 dlm_send_rcom_lookup_dump(r, from_nodeid);
1007 goto out_found;
1008 }
1009
1010 r->res_master_nodeid = from_nodeid;
1011 r->res_nodeid = from_nodeid;
1012 rsb_set_flag(r, RSB_NEW_MASTER);
1013 }
1014
1015 if (!r->res_master_nodeid) {
1016 /* this will happen if recovery happens while we're looking
1017 up the master for this rsb */
1018
1019 log_debug(ls, "dlm_master_lookup master 0 to %d first %x %s",
1020 from_nodeid, r->res_first_lkid, r->res_name);
1021 r->res_master_nodeid = from_nodeid;
1022 r->res_nodeid = from_nodeid;
1023 }
1024
1025 if (!from_master && !fix_master &&
1026 (r->res_master_nodeid == from_nodeid)) {
1027 /* this can happen when the master sends remove, the dir node
1028 finds the rsb on the keep list and ignores the remove,
1029 and the former master sends a lookup */
1030
1031 log_limit(ls, "dlm_master_lookup from master %d flags %x "
1032 "first %x %s", from_nodeid, flags,
1033 r->res_first_lkid, r->res_name);
1034 }
1035
1036 out_found:
1037 *r_nodeid = r->res_master_nodeid;
1038 if (result)
1039 *result = DLM_LU_MATCH;
1040
1041 if (toss_list) {
1042 r->res_toss_time = jiffies;
1043 /* the rsb was inactive (on toss list) */
1044 spin_unlock(&ls->ls_rsbtbl[b].lock);
1045 } else {
1046 /* the rsb was active */
1047 unlock_rsb(r);
1048 put_rsb(r);
1049 }
1050 return 0;
e7fd4179 1051
c04fecb4
DT		 1052 not_found:
1053 error = get_rsb_struct(ls, name, len, &r);
3881ac04 1054 if (error == -EAGAIN) {
c04fecb4 1055 spin_unlock(&ls->ls_rsbtbl[b].lock);
3881ac04
DT		 1056 goto retry;
1057 }
1058 if (error)
1059 goto out_unlock;
e7fd4179
DT		 1060
1061 r->res_hash = hash;
c04fecb4
DT		 1062 r->res_bucket = b;
1063 r->res_dir_nodeid = our_nodeid;
1064 r->res_master_nodeid = from_nodeid;
1065 r->res_nodeid = from_nodeid;
e7fd4179 1066 kref_init(&r->res_ref);
c04fecb4 1067 r->res_toss_time = jiffies;
e7fd4179 1068
c04fecb4
DT		 1069 error = rsb_insert(r, &ls->ls_rsbtbl[b].toss);
1070 if (error) {
1071 /* should never happen */
1072 dlm_free_rsb(r);
1073 spin_unlock(&ls->ls_rsbtbl[b].lock);
1074 goto retry;
e7fd4179 1075 }
c04fecb4
DT		 1076
1077 if (result)
1078 *result = DLM_LU_ADD;
1079 *r_nodeid = from_nodeid;
1080 error = 0;
3881ac04 1081 out_unlock:
c04fecb4 1082 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1083 return error;
1084}
1085
6d40c4a7
DT		 1086static void dlm_dump_rsb_hash(struct dlm_ls *ls, uint32_t hash)
1087{
1088 struct rb_node *n;
1089 struct dlm_rsb *r;
1090 int i;
1091
1092 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1093 spin_lock(&ls->ls_rsbtbl[i].lock);
1094 for (n = rb_first(&ls->ls_rsbtbl[i].keep); n; n = rb_next(n)) {
1095 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1096 if (r->res_hash == hash)
1097 dlm_dump_rsb(r);
1098 }
1099 spin_unlock(&ls->ls_rsbtbl[i].lock);
1100 }
1101}
1102
c04fecb4 1103void dlm_dump_rsb_name(struct dlm_ls *ls, char *name, int len)
e7fd4179 1104{
c04fecb4
DT		 1105 struct dlm_rsb *r = NULL;
1106 uint32_t hash, b;
1107 int error;
e7fd4179 1108
c04fecb4
DT		 1109 hash = jhash(name, len, 0);
1110 b = hash & (ls->ls_rsbtbl_size - 1);
1111
1112 spin_lock(&ls->ls_rsbtbl[b].lock);
1113 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
1114 if (!error)
1115 goto out_dump;
1116
1117 error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1118 if (error)
1119 goto out;
1120 out_dump:
1121 dlm_dump_rsb(r);
1122 out:
1123 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179
DT		 1124}
1125
1126static void toss_rsb(struct kref *kref)
1127{
1128 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1129 struct dlm_ls *ls = r->res_ls;
1130
1131 DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r););
1132 kref_init(&r->res_ref);
9beb3bf5
BP		 1133 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[r->res_bucket].keep);
1134 rsb_insert(r, &ls->ls_rsbtbl[r->res_bucket].toss);
e7fd4179 1135 r->res_toss_time = jiffies;
f1172283 1136 ls->ls_rsbtbl[r->res_bucket].flags |= DLM_RTF_SHRINK;
e7fd4179 1137 if (r->res_lvbptr) {
52bda2b5 1138 dlm_free_lvb(r->res_lvbptr);
e7fd4179
DT		 1139 r->res_lvbptr = NULL;
1140 }
1141}
1142
e7fd4179
DT		 1143/* See comment for unhold_lkb */
1144
1145static void unhold_rsb(struct dlm_rsb *r)
1146{
1147 int rv;
1148 rv = kref_put(&r->res_ref, toss_rsb);
a345da3e 1149 DLM_ASSERT(!rv, dlm_dump_rsb(r););
e7fd4179
DT		 1150}
1151
1152static void kill_rsb(struct kref *kref)
1153{
1154 struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref);
1155
1156 /* All work is done after the return from kref_put() so we
1157 can release the write_lock before the remove and free. */
1158
a345da3e
DT		 1159 DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r););
1160 DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r););
1161 DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r););
1162 DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r););
1163 DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r););
1164 DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r););
e7fd4179
DT		 1165}
1166
1167/* Attaching/detaching lkb's from rsb's is for rsb reference counting.
1168 The rsb must exist as long as any lkb's for it do. */
1169
1170static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1171{
1172 hold_rsb(r);
1173 lkb->lkb_resource = r;
1174}
1175
1176static void detach_lkb(struct dlm_lkb *lkb)
1177{
1178 if (lkb->lkb_resource) {
1179 put_rsb(lkb->lkb_resource);
1180 lkb->lkb_resource = NULL;
1181 }
1182}
1183
1184static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
1185{
3d6aa675 1186 struct dlm_lkb *lkb;
2a86b3e7 1187 int rv;
e7fd4179 1188
52bda2b5 1189 lkb = dlm_allocate_lkb(ls);
e7fd4179
DT		 1190 if (!lkb)
1191 return -ENOMEM;
1192
1193 lkb->lkb_nodeid = -1;
1194 lkb->lkb_grmode = DLM_LOCK_IV;
1195 kref_init(&lkb->lkb_ref);
34e22bed 1196 INIT_LIST_HEAD(&lkb->lkb_ownqueue);
ef0c2bb0 1197 INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
3ae1acf9 1198 INIT_LIST_HEAD(&lkb->lkb_time_list);
23e8e1aa
DT		 1199 INIT_LIST_HEAD(&lkb->lkb_cb_list);
1200 mutex_init(&lkb->lkb_cb_mutex);
1201 INIT_WORK(&lkb->lkb_cb_work, dlm_callback_work);
e7fd4179 1202
2a86b3e7 1203 idr_preload(GFP_NOFS);
3d6aa675 1204 spin_lock(&ls->ls_lkbidr_spin);
2a86b3e7
TH		 1205 rv = idr_alloc(&ls->ls_lkbidr, lkb, 1, 0, GFP_NOWAIT);
1206 if (rv >= 0)
1207 lkb->lkb_id = rv;
3d6aa675 1208 spin_unlock(&ls->ls_lkbidr_spin);
2a86b3e7 1209 idr_preload_end();
e7fd4179 1210
3d6aa675
DT		 1211 if (rv < 0) {
1212 log_error(ls, "create_lkb idr error %d", rv);
1213 return rv;
e7fd4179
DT		 1214 }
1215
e7fd4179
DT		 1216 *lkb_ret = lkb;
1217 return 0;
1218}
1219
e7fd4179
DT		 1220static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
1221{
1222 struct dlm_lkb *lkb;
e7fd4179 1223
3d6aa675
DT		 1224 spin_lock(&ls->ls_lkbidr_spin);
1225 lkb = idr_find(&ls->ls_lkbidr, lkid);
e7fd4179
DT		 1226 if (lkb)
1227 kref_get(&lkb->lkb_ref);
3d6aa675 1228 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 1229
1230 *lkb_ret = lkb;
1231 return lkb ? 0 : -ENOENT;
1232}
1233
1234static void kill_lkb(struct kref *kref)
1235{
1236 struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref);
1237
1238 /* All work is done after the return from kref_put() so we
1239 can release the write_lock before the detach_lkb */
1240
1241 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1242}
1243
b3f58d8f
DT		 1244/* __put_lkb() is used when an lkb may not have an rsb attached to
1245 it so we need to provide the lockspace explicitly */
1246
1247static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
e7fd4179 1248{
3d6aa675 1249 uint32_t lkid = lkb->lkb_id;
e7fd4179 1250
3d6aa675 1251 spin_lock(&ls->ls_lkbidr_spin);
e7fd4179 1252 if (kref_put(&lkb->lkb_ref, kill_lkb)) {
3d6aa675
DT		 1253 idr_remove(&ls->ls_lkbidr, lkid);
1254 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 1255
1256 detach_lkb(lkb);
1257
1258 /* for local/process lkbs, lvbptr points to caller's lksb */
1259 if (lkb->lkb_lvbptr && is_master_copy(lkb))
52bda2b5
DT		 1260 dlm_free_lvb(lkb->lkb_lvbptr);
1261 dlm_free_lkb(lkb);
e7fd4179
DT		 1262 return 1;
1263 } else {
3d6aa675 1264 spin_unlock(&ls->ls_lkbidr_spin);
e7fd4179
DT		 1265 return 0;
1266 }
1267}
1268
1269int dlm_put_lkb(struct dlm_lkb *lkb)
1270{
b3f58d8f
DT		 1271 struct dlm_ls *ls;
1272
1273 DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb););
1274 DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb););
1275
1276 ls = lkb->lkb_resource->res_ls;
1277 return __put_lkb(ls, lkb);
e7fd4179
DT		 1278}
1279
1280/* This is only called to add a reference when the code already holds
1281 a valid reference to the lkb, so there's no need for locking. */
1282
1283static inline void hold_lkb(struct dlm_lkb *lkb)
1284{
1285 kref_get(&lkb->lkb_ref);
1286}
1287
1288/* This is called when we need to remove a reference and are certain
1289 it's not the last ref. e.g. del_lkb is always called between a
1290 find_lkb/put_lkb and is always the inverse of a previous add_lkb.
1291 put_lkb would work fine, but would involve unnecessary locking */
1292
1293static inline void unhold_lkb(struct dlm_lkb *lkb)
1294{
1295 int rv;
1296 rv = kref_put(&lkb->lkb_ref, kill_lkb);
1297 DLM_ASSERT(!rv, dlm_print_lkb(lkb););
1298}
1299
1300static void lkb_add_ordered(struct list_head *new, struct list_head *head,
1301 int mode)
1302{
1303 struct dlm_lkb *lkb = NULL;
1304
1305 list_for_each_entry(lkb, head, lkb_statequeue)
1306 if (lkb->lkb_rqmode < mode)
1307 break;
1308
99fb19d4 1309 __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue);
e7fd4179
DT		 1310}
1311
1312/* add/remove lkb to rsb's grant/convert/wait queue */
1313
1314static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status)
1315{
1316 kref_get(&lkb->lkb_ref);
1317
1318 DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
1319
eeda418d
DT		 1320 lkb->lkb_timestamp = ktime_get();
1321
e7fd4179
DT		 1322 lkb->lkb_status = status;
1323
1324 switch (status) {
1325 case DLM_LKSTS_WAITING:
1326 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1327 list_add(&lkb->lkb_statequeue, &r->res_waitqueue);
1328 else
1329 list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue);
1330 break;
1331 case DLM_LKSTS_GRANTED:
1332 /* convention says granted locks kept in order of grmode */
1333 lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue,
1334 lkb->lkb_grmode);
1335 break;
1336 case DLM_LKSTS_CONVERT:
1337 if (lkb->lkb_exflags & DLM_LKF_HEADQUE)
1338 list_add(&lkb->lkb_statequeue, &r->res_convertqueue);
1339 else
1340 list_add_tail(&lkb->lkb_statequeue,
1341 &r->res_convertqueue);
1342 break;
1343 default:
1344 DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status););
1345 }
1346}
1347
1348static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb)
1349{
1350 lkb->lkb_status = 0;
1351 list_del(&lkb->lkb_statequeue);
1352 unhold_lkb(lkb);
1353}
1354
1355static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts)
1356{
1357 hold_lkb(lkb);
1358 del_lkb(r, lkb);
1359 add_lkb(r, lkb, sts);
1360 unhold_lkb(lkb);
1361}
1362
ef0c2bb0
DT		 1363static int msg_reply_type(int mstype)
1364{
1365 switch (mstype) {
1366 case DLM_MSG_REQUEST:
1367 return DLM_MSG_REQUEST_REPLY;
1368 case DLM_MSG_CONVERT:
1369 return DLM_MSG_CONVERT_REPLY;
1370 case DLM_MSG_UNLOCK:
1371 return DLM_MSG_UNLOCK_REPLY;
1372 case DLM_MSG_CANCEL:
1373 return DLM_MSG_CANCEL_REPLY;
1374 case DLM_MSG_LOOKUP:
1375 return DLM_MSG_LOOKUP_REPLY;
1376 }
1377 return -1;
1378}
1379
c6ff669b
DT		 1380static int nodeid_warned(int nodeid, int num_nodes, int *warned)
1381{
1382 int i;
1383
1384 for (i = 0; i < num_nodes; i++) {
1385 if (!warned[i]) {
1386 warned[i] = nodeid;
1387 return 0;
1388 }
1389 if (warned[i] == nodeid)
1390 return 1;
1391 }
1392 return 0;
1393}
1394
1395void dlm_scan_waiters(struct dlm_ls *ls)
1396{
1397 struct dlm_lkb *lkb;
1398 ktime_t zero = ktime_set(0, 0);
1399 s64 us;
1400 s64 debug_maxus = 0;
1401 u32 debug_scanned = 0;
1402 u32 debug_expired = 0;
1403 int num_nodes = 0;
1404 int *warned = NULL;
1405
1406 if (!dlm_config.ci_waitwarn_us)
1407 return;
1408
1409 mutex_lock(&ls->ls_waiters_mutex);
1410
1411 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1412 if (ktime_equal(lkb->lkb_wait_time, zero))
1413 continue;
1414
1415 debug_scanned++;
1416
1417 us = ktime_to_us(ktime_sub(ktime_get(), lkb->lkb_wait_time));
1418
1419 if (us < dlm_config.ci_waitwarn_us)
1420 continue;
1421
1422 lkb->lkb_wait_time = zero;
1423
1424 debug_expired++;
1425 if (us > debug_maxus)
1426 debug_maxus = us;
1427
1428 if (!num_nodes) {
1429 num_nodes = ls->ls_num_nodes;
5d70828a 1430 warned = kzalloc(num_nodes * sizeof(int), GFP_KERNEL);
c6ff669b
DT		 1431 }
1432 if (!warned)
1433 continue;
1434 if (nodeid_warned(lkb->lkb_wait_nodeid, num_nodes, warned))
1435 continue;
1436
1437 log_error(ls, "waitwarn %x %lld %d us check connection to "
1438 "node %d", lkb->lkb_id, (long long)us,
1439 dlm_config.ci_waitwarn_us, lkb->lkb_wait_nodeid);
1440 }
1441 mutex_unlock(&ls->ls_waiters_mutex);
5d70828a 1442 kfree(warned);
c6ff669b
DT		 1443
1444 if (debug_expired)
1445 log_debug(ls, "scan_waiters %u warn %u over %d us max %lld us",
1446 debug_scanned, debug_expired,
1447 dlm_config.ci_waitwarn_us, (long long)debug_maxus);
1448}
1449
e7fd4179
DT		 1450/* add/remove lkb from global waiters list of lkb's waiting for
1451 a reply from a remote node */
1452
c6ff669b 1453static int add_to_waiters(struct dlm_lkb *lkb, int mstype, int to_nodeid)
e7fd4179
DT		 1454{
1455 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
ef0c2bb0 1456 int error = 0;
e7fd4179 1457
90135925 1458 mutex_lock(&ls->ls_waiters_mutex);
ef0c2bb0
DT		 1459
1460 if (is_overlap_unlock(lkb) ||
1461 (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL))) {
1462 error = -EINVAL;
1463 goto out;
1464 }
1465
1466 if (lkb->lkb_wait_type || is_overlap_cancel(lkb)) {
1467 switch (mstype) {
1468 case DLM_MSG_UNLOCK:
1469 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
1470 break;
1471 case DLM_MSG_CANCEL:
1472 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
1473 break;
1474 default:
1475 error = -EBUSY;
1476 goto out;
1477 }
1478 lkb->lkb_wait_count++;
1479 hold_lkb(lkb);
1480
43279e53 1481 log_debug(ls, "addwait %x cur %d overlap %d count %d f %x",
ef0c2bb0
DT		 1482 lkb->lkb_id, lkb->lkb_wait_type, mstype,
1483 lkb->lkb_wait_count, lkb->lkb_flags);
e7fd4179
DT		 1484 goto out;
1485 }
ef0c2bb0
DT		 1486
1487 DLM_ASSERT(!lkb->lkb_wait_count,
1488 dlm_print_lkb(lkb);
1489 printk("wait_count %d\n", lkb->lkb_wait_count););
1490
1491 lkb->lkb_wait_count++;
e7fd4179 1492 lkb->lkb_wait_type = mstype;
c6ff669b
DT		 1493 lkb->lkb_wait_time = ktime_get();
1494 lkb->lkb_wait_nodeid = to_nodeid; /* for debugging */
ef0c2bb0 1495 hold_lkb(lkb);
e7fd4179
DT		 1496 list_add(&lkb->lkb_wait_reply, &ls->ls_waiters);
1497 out:
ef0c2bb0 1498 if (error)
43279e53 1499 log_error(ls, "addwait error %x %d flags %x %d %d %s",
ef0c2bb0
DT		 1500 lkb->lkb_id, error, lkb->lkb_flags, mstype,
1501 lkb->lkb_wait_type, lkb->lkb_resource->res_name);
90135925 1502 mutex_unlock(&ls->ls_waiters_mutex);
ef0c2bb0 1503 return error;
e7fd4179
DT		 1504}
1505
b790c3b7
DT		 1506/* We clear the RESEND flag because we might be taking an lkb off the waiters
1507 list as part of process_requestqueue (e.g. a lookup that has an optimized
1508 request reply on the requestqueue) between dlm_recover_waiters_pre() which
1509 set RESEND and dlm_recover_waiters_post() */
1510
43279e53
DT		 1511static int _remove_from_waiters(struct dlm_lkb *lkb, int mstype,
1512 struct dlm_message *ms)
e7fd4179 1513{
ef0c2bb0
DT		 1514 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1515 int overlap_done = 0;
e7fd4179 1516
ef0c2bb0 1517 if (is_overlap_unlock(lkb) && (mstype == DLM_MSG_UNLOCK_REPLY)) {
43279e53 1518 log_debug(ls, "remwait %x unlock_reply overlap", lkb->lkb_id);
ef0c2bb0
DT		 1519 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
1520 overlap_done = 1;
1521 goto out_del;
e7fd4179 1522 }
ef0c2bb0
DT		 1523
1524 if (is_overlap_cancel(lkb) && (mstype == DLM_MSG_CANCEL_REPLY)) {
43279e53 1525 log_debug(ls, "remwait %x cancel_reply overlap", lkb->lkb_id);
ef0c2bb0
DT		 1526 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1527 overlap_done = 1;
1528 goto out_del;
1529 }
1530
43279e53
DT		 1531 /* Cancel state was preemptively cleared by a successful convert,
1532 see next comment, nothing to do. */
1533
1534 if ((mstype == DLM_MSG_CANCEL_REPLY) &&
1535 (lkb->lkb_wait_type != DLM_MSG_CANCEL)) {
1536 log_debug(ls, "remwait %x cancel_reply wait_type %d",
1537 lkb->lkb_id, lkb->lkb_wait_type);
1538 return -1;
1539 }
1540
1541 /* Remove for the convert reply, and premptively remove for the
1542 cancel reply. A convert has been granted while there's still
1543 an outstanding cancel on it (the cancel is moot and the result
1544 in the cancel reply should be 0). We preempt the cancel reply
1545 because the app gets the convert result and then can follow up
1546 with another op, like convert. This subsequent op would see the
1547 lingering state of the cancel and fail with -EBUSY. */
1548
1549 if ((mstype == DLM_MSG_CONVERT_REPLY) &&
1550 (lkb->lkb_wait_type == DLM_MSG_CONVERT) &&
1551 is_overlap_cancel(lkb) && ms && !ms->m_result) {
1552 log_debug(ls, "remwait %x convert_reply zap overlap_cancel",
1553 lkb->lkb_id);
1554 lkb->lkb_wait_type = 0;
1555 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
1556 lkb->lkb_wait_count--;
1557 goto out_del;
1558 }
1559
ef0c2bb0
DT		 1560 /* N.B. type of reply may not always correspond to type of original
1561 msg due to lookup->request optimization, verify others? */
1562
1563 if (lkb->lkb_wait_type) {
1564 lkb->lkb_wait_type = 0;
1565 goto out_del;
1566 }
1567
6d40c4a7
DT		 1568 log_error(ls, "remwait error %x remote %d %x msg %d flags %x no wait",
1569 lkb->lkb_id, ms ? ms->m_header.h_nodeid : 0, lkb->lkb_remid,
1570 mstype, lkb->lkb_flags);
ef0c2bb0
DT		 1571 return -1;
1572
1573 out_del:
1574 /* the force-unlock/cancel has completed and we haven't recvd a reply
1575 to the op that was in progress prior to the unlock/cancel; we
1576 give up on any reply to the earlier op. FIXME: not sure when/how
1577 this would happen */
1578
1579 if (overlap_done && lkb->lkb_wait_type) {
43279e53 1580 log_error(ls, "remwait error %x reply %d wait_type %d overlap",
ef0c2bb0
DT		 1581 lkb->lkb_id, mstype, lkb->lkb_wait_type);
1582 lkb->lkb_wait_count--;
1583 lkb->lkb_wait_type = 0;
1584 }
1585
1586 DLM_ASSERT(lkb->lkb_wait_count, dlm_print_lkb(lkb););
1587
b790c3b7 1588 lkb->lkb_flags &= ~DLM_IFL_RESEND;
ef0c2bb0
DT		 1589 lkb->lkb_wait_count--;
1590 if (!lkb->lkb_wait_count)
1591 list_del_init(&lkb->lkb_wait_reply);
e7fd4179 1592 unhold_lkb(lkb);
ef0c2bb0 1593 return 0;
e7fd4179
DT		 1594}
1595
ef0c2bb0 1596static int remove_from_waiters(struct dlm_lkb *lkb, int mstype)
e7fd4179
DT		 1597{
1598 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1599 int error;
1600
90135925 1601 mutex_lock(&ls->ls_waiters_mutex);
43279e53 1602 error = _remove_from_waiters(lkb, mstype, NULL);
90135925 1603 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179
DT		 1604 return error;
1605}
1606
ef0c2bb0
DT		 1607/* Handles situations where we might be processing a "fake" or "stub" reply in
1608 which we can't try to take waiters_mutex again. */
1609
1610static int remove_from_waiters_ms(struct dlm_lkb *lkb, struct dlm_message *ms)
1611{
1612 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1613 int error;
1614
2a7ce0ed 1615 if (ms->m_flags != DLM_IFL_STUB_MS)
ef0c2bb0 1616 mutex_lock(&ls->ls_waiters_mutex);
43279e53 1617 error = _remove_from_waiters(lkb, ms->m_type, ms);
2a7ce0ed 1618 if (ms->m_flags != DLM_IFL_STUB_MS)
ef0c2bb0
DT		 1619 mutex_unlock(&ls->ls_waiters_mutex);
1620 return error;
1621}
1622
05c32f47
DT		 1623/* If there's an rsb for the same resource being removed, ensure
1624 that the remove message is sent before the new lookup message.
1625 It should be rare to need a delay here, but if not, then it may
1626 be worthwhile to add a proper wait mechanism rather than a delay. */
e7fd4179 1627
05c32f47 1628static void wait_pending_remove(struct dlm_rsb *r)
e7fd4179 1629{
05c32f47
DT		 1630 struct dlm_ls *ls = r->res_ls;
1631 restart:
1632 spin_lock(&ls->ls_remove_spin);
1633 if (ls->ls_remove_len &&
1634 !rsb_cmp(r, ls->ls_remove_name, ls->ls_remove_len)) {
1635 log_debug(ls, "delay lookup for remove dir %d %s",
1636 r->res_dir_nodeid, r->res_name);
1637 spin_unlock(&ls->ls_remove_spin);
1638 msleep(1);
1639 goto restart;
1640 }
1641 spin_unlock(&ls->ls_remove_spin);
1642}
e7fd4179 1643
05c32f47
DT		 1644/*
1645 * ls_remove_spin protects ls_remove_name and ls_remove_len which are
1646 * read by other threads in wait_pending_remove. ls_remove_names
1647 * and ls_remove_lens are only used by the scan thread, so they do
1648 * not need protection.
1649 */
c04fecb4 1650
05c32f47
DT		 1651static void shrink_bucket(struct dlm_ls *ls, int b)
1652{
1653 struct rb_node *n, *next;
1654 struct dlm_rsb *r;
1655 char *name;
1656 int our_nodeid = dlm_our_nodeid();
1657 int remote_count = 0;
f1172283 1658 int need_shrink = 0;
05c32f47 1659 int i, len, rv;
c04fecb4 1660
05c32f47 1661 memset(&ls->ls_remove_lens, 0, sizeof(int) * DLM_REMOVE_NAMES_MAX);
c04fecb4 1662
05c32f47 1663 spin_lock(&ls->ls_rsbtbl[b].lock);
f1172283
DT		 1664
1665 if (!(ls->ls_rsbtbl[b].flags & DLM_RTF_SHRINK)) {
1666 spin_unlock(&ls->ls_rsbtbl[b].lock);
1667 return;
1668 }
1669
05c32f47
DT		 1670 for (n = rb_first(&ls->ls_rsbtbl[b].toss); n; n = next) {
1671 next = rb_next(n);
1672 r = rb_entry(n, struct dlm_rsb, res_hashnode);
1673
1674 /* If we're the directory record for this rsb, and
1675 we're not the master of it, then we need to wait
1676 for the master node to send us a dir remove for
1677 before removing the dir record. */
1678
1679 if (!dlm_no_directory(ls) &&
1680 (r->res_master_nodeid != our_nodeid) &&
1681 (dlm_dir_nodeid(r) == our_nodeid)) {
1682 continue;
e7fd4179
DT		 1683 }
1684
f1172283
DT		 1685 need_shrink = 1;
1686
05c32f47
DT		 1687 if (!time_after_eq(jiffies, r->res_toss_time +
1688 dlm_config.ci_toss_secs * HZ)) {
1689 continue;
e7fd4179
DT		 1690 }
1691
05c32f47
DT		 1692 if (!dlm_no_directory(ls) &&
1693 (r->res_master_nodeid == our_nodeid) &&
1694 (dlm_dir_nodeid(r) != our_nodeid)) {
e7fd4179 1695
c04fecb4
DT		 1696 /* We're the master of this rsb but we're not
1697 the directory record, so we need to tell the
1698 dir node to remove the dir record. */
1699
05c32f47
DT		 1700 ls->ls_remove_lens[remote_count] = r->res_length;
1701 memcpy(ls->ls_remove_names[remote_count], r->res_name,
1702 DLM_RESNAME_MAXLEN);
1703 remote_count++;
c04fecb4 1704
05c32f47
DT		 1705 if (remote_count >= DLM_REMOVE_NAMES_MAX)
1706 break;
1707 continue;
1708 }
1709
1710 if (!kref_put(&r->res_ref, kill_rsb)) {
e7fd4179 1711 log_error(ls, "tossed rsb in use %s", r->res_name);
05c32f47 1712 continue;
e7fd4179 1713 }
05c32f47
DT		 1714
1715 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1716 dlm_free_rsb(r);
e7fd4179 1717 }
f1172283
DT		 1718
1719 if (need_shrink)
1720 ls->ls_rsbtbl[b].flags |= DLM_RTF_SHRINK;
1721 else
1722 ls->ls_rsbtbl[b].flags &= ~DLM_RTF_SHRINK;
05c32f47 1723 spin_unlock(&ls->ls_rsbtbl[b].lock);
e7fd4179 1724
05c32f47
DT		 1725 /*
1726 * While searching for rsb's to free, we found some that require
1727 * remote removal. We leave them in place and find them again here
1728 * so there is a very small gap between removing them from the toss
1729 * list and sending the removal. Keeping this gap small is
1730 * important to keep us (the master node) from being out of sync
1731 * with the remote dir node for very long.
1732 *
1733 * From the time the rsb is removed from toss until just after
1734 * send_remove, the rsb name is saved in ls_remove_name. A new
1735 * lookup checks this to ensure that a new lookup message for the
1736 * same resource name is not sent just before the remove message.
1737 */
1738
1739 for (i = 0; i < remote_count; i++) {
1740 name = ls->ls_remove_names[i];
1741 len = ls->ls_remove_lens[i];
1742
1743 spin_lock(&ls->ls_rsbtbl[b].lock);
1744 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
1745 if (rv) {
1746 spin_unlock(&ls->ls_rsbtbl[b].lock);
1747 log_debug(ls, "remove_name not toss %s", name);
1748 continue;
1749 }
1750
1751 if (r->res_master_nodeid != our_nodeid) {
1752 spin_unlock(&ls->ls_rsbtbl[b].lock);
1753 log_debug(ls, "remove_name master %d dir %d our %d %s",
1754 r->res_master_nodeid, r->res_dir_nodeid,
1755 our_nodeid, name);
1756 continue;
1757 }
1758
1759 if (r->res_dir_nodeid == our_nodeid) {
1760 /* should never happen */
1761 spin_unlock(&ls->ls_rsbtbl[b].lock);
1762 log_error(ls, "remove_name dir %d master %d our %d %s",
1763 r->res_dir_nodeid, r->res_master_nodeid,
1764 our_nodeid, name);
1765 continue;
1766 }
1767
1768 if (!time_after_eq(jiffies, r->res_toss_time +
1769 dlm_config.ci_toss_secs * HZ)) {
1770 spin_unlock(&ls->ls_rsbtbl[b].lock);
1771 log_debug(ls, "remove_name toss_time %lu now %lu %s",
1772 r->res_toss_time, jiffies, name);
1773 continue;
1774 }
1775
1776 if (!kref_put(&r->res_ref, kill_rsb)) {
1777 spin_unlock(&ls->ls_rsbtbl[b].lock);
1778 log_error(ls, "remove_name in use %s", name);
1779 continue;
1780 }
1781
1782 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
1783
1784 /* block lookup of same name until we've sent remove */
1785 spin_lock(&ls->ls_remove_spin);
1786 ls->ls_remove_len = len;
1787 memcpy(ls->ls_remove_name, name, DLM_RESNAME_MAXLEN);
1788 spin_unlock(&ls->ls_remove_spin);
1789 spin_unlock(&ls->ls_rsbtbl[b].lock);
1790
1791 send_remove(r);
1792
1793 /* allow lookup of name again */
1794 spin_lock(&ls->ls_remove_spin);
1795 ls->ls_remove_len = 0;
1796 memset(ls->ls_remove_name, 0, DLM_RESNAME_MAXLEN);
1797 spin_unlock(&ls->ls_remove_spin);
1798
1799 dlm_free_rsb(r);
1800 }
e7fd4179
DT		 1801}
1802
1803void dlm_scan_rsbs(struct dlm_ls *ls)
1804{
1805 int i;
1806
e7fd4179
DT		 1807 for (i = 0; i < ls->ls_rsbtbl_size; i++) {
1808 shrink_bucket(ls, i);
85e86edf
DT		 1809 if (dlm_locking_stopped(ls))
1810 break;
e7fd4179
DT		 1811 cond_resched();
1812 }
1813}
1814
3ae1acf9
DT		 1815static void add_timeout(struct dlm_lkb *lkb)
1816{
1817 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1818
eeda418d 1819 if (is_master_copy(lkb))
3ae1acf9 1820 return;
3ae1acf9
DT		 1821
1822 if (test_bit(LSFL_TIMEWARN, &ls->ls_flags) &&
1823 !(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
1824 lkb->lkb_flags |= DLM_IFL_WATCH_TIMEWARN;
1825 goto add_it;
1826 }
84d8cd69
DT		 1827 if (lkb->lkb_exflags & DLM_LKF_TIMEOUT)
1828 goto add_it;
3ae1acf9
DT		 1829 return;
1830
1831 add_it:
1832 DLM_ASSERT(list_empty(&lkb->lkb_time_list), dlm_print_lkb(lkb););
1833 mutex_lock(&ls->ls_timeout_mutex);
1834 hold_lkb(lkb);
3ae1acf9
DT		 1835 list_add_tail(&lkb->lkb_time_list, &ls->ls_timeout);
1836 mutex_unlock(&ls->ls_timeout_mutex);
1837}
1838
1839static void del_timeout(struct dlm_lkb *lkb)
1840{
1841 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
1842
1843 mutex_lock(&ls->ls_timeout_mutex);
1844 if (!list_empty(&lkb->lkb_time_list)) {
1845 list_del_init(&lkb->lkb_time_list);
1846 unhold_lkb(lkb);
1847 }
1848 mutex_unlock(&ls->ls_timeout_mutex);
1849}
1850
1851/* FIXME: is it safe to look at lkb_exflags, lkb_flags, lkb_timestamp, and
1852 lkb_lksb_timeout without lock_rsb? Note: we can't lock timeout_mutex
1853 and then lock rsb because of lock ordering in add_timeout. We may need
1854 to specify some special timeout-related bits in the lkb that are just to
1855 be accessed under the timeout_mutex. */
1856
1857void dlm_scan_timeout(struct dlm_ls *ls)
1858{
1859 struct dlm_rsb *r;
1860 struct dlm_lkb *lkb;
1861 int do_cancel, do_warn;
eeda418d 1862 s64 wait_us;
3ae1acf9
DT		 1863
1864 for (;;) {
1865 if (dlm_locking_stopped(ls))
1866 break;
1867
1868 do_cancel = 0;
1869 do_warn = 0;
1870 mutex_lock(&ls->ls_timeout_mutex);
1871 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
1872
eeda418d
DT		 1873 wait_us = ktime_to_us(ktime_sub(ktime_get(),
1874 lkb->lkb_timestamp));
1875
3ae1acf9 1876 if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
eeda418d 1877 wait_us >= (lkb->lkb_timeout_cs * 10000))
3ae1acf9
DT		 1878 do_cancel = 1;
1879
1880 if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
eeda418d 1881 wait_us >= dlm_config.ci_timewarn_cs * 10000)
3ae1acf9
DT		 1882 do_warn = 1;
1883
1884 if (!do_cancel && !do_warn)
1885 continue;
1886 hold_lkb(lkb);
1887 break;
1888 }
1889 mutex_unlock(&ls->ls_timeout_mutex);
1890
1891 if (!do_cancel && !do_warn)
1892 break;
1893
1894 r = lkb->lkb_resource;
1895 hold_rsb(r);
1896 lock_rsb(r);
1897
1898 if (do_warn) {
1899 /* clear flag so we only warn once */
1900 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1901 if (!(lkb->lkb_exflags & DLM_LKF_TIMEOUT))
1902 del_timeout(lkb);
1903 dlm_timeout_warn(lkb);
1904 }
1905
1906 if (do_cancel) {
b3cab7b9 1907 log_debug(ls, "timeout cancel %x node %d %s",
639aca41 1908 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
3ae1acf9
DT		 1909 lkb->lkb_flags &= ~DLM_IFL_WATCH_TIMEWARN;
1910 lkb->lkb_flags |= DLM_IFL_TIMEOUT_CANCEL;
1911 del_timeout(lkb);
1912 _cancel_lock(r, lkb);
1913 }
1914
1915 unlock_rsb(r);
1916 unhold_rsb(r);
1917 dlm_put_lkb(lkb);
1918 }
1919}
1920
1921/* This is only called by dlm_recoverd, and we rely on dlm_ls_stop() stopping
1922 dlm_recoverd before checking/setting ls_recover_begin. */
1923
1924void dlm_adjust_timeouts(struct dlm_ls *ls)
1925{
1926 struct dlm_lkb *lkb;
eeda418d 1927 u64 adj_us = jiffies_to_usecs(jiffies - ls->ls_recover_begin);
3ae1acf9
DT		 1928
1929 ls->ls_recover_begin = 0;
1930 mutex_lock(&ls->ls_timeout_mutex);
1931 list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list)
eeda418d 1932 lkb->lkb_timestamp = ktime_add_us(lkb->lkb_timestamp, adj_us);
3ae1acf9 1933 mutex_unlock(&ls->ls_timeout_mutex);
c6ff669b
DT		 1934
1935 if (!dlm_config.ci_waitwarn_us)
1936 return;
1937
1938 mutex_lock(&ls->ls_waiters_mutex);
1939 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
1940 if (ktime_to_us(lkb->lkb_wait_time))
1941 lkb->lkb_wait_time = ktime_get();
1942 }
1943 mutex_unlock(&ls->ls_waiters_mutex);
3ae1acf9
DT		 1944}
1945
e7fd4179
DT		 1946/* lkb is master or local copy */
1947
1948static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
1949{
1950 int b, len = r->res_ls->ls_lvblen;
1951
1952 /* b=1 lvb returned to caller
1953 b=0 lvb written to rsb or invalidated
1954 b=-1 do nothing */
1955
1956 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
1957
1958 if (b == 1) {
1959 if (!lkb->lkb_lvbptr)
1960 return;
1961
1962 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1963 return;
1964
1965 if (!r->res_lvbptr)
1966 return;
1967
1968 memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len);
1969 lkb->lkb_lvbseq = r->res_lvbseq;
1970
1971 } else if (b == 0) {
1972 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
1973 rsb_set_flag(r, RSB_VALNOTVALID);
1974 return;
1975 }
1976
1977 if (!lkb->lkb_lvbptr)
1978 return;
1979
1980 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
1981 return;
1982
1983 if (!r->res_lvbptr)
52bda2b5 1984 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 1985
1986 if (!r->res_lvbptr)
1987 return;
1988
1989 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len);
1990 r->res_lvbseq++;
1991 lkb->lkb_lvbseq = r->res_lvbseq;
1992 rsb_clear_flag(r, RSB_VALNOTVALID);
1993 }
1994
1995 if (rsb_flag(r, RSB_VALNOTVALID))
1996 lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID;
1997}
1998
1999static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2000{
2001 if (lkb->lkb_grmode < DLM_LOCK_PW)
2002 return;
2003
2004 if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) {
2005 rsb_set_flag(r, RSB_VALNOTVALID);
2006 return;
2007 }
2008
2009 if (!lkb->lkb_lvbptr)
2010 return;
2011
2012 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
2013 return;
2014
2015 if (!r->res_lvbptr)
52bda2b5 2016 r->res_lvbptr = dlm_allocate_lvb(r->res_ls);
e7fd4179
DT		 2017
2018 if (!r->res_lvbptr)
2019 return;
2020
2021 memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
2022 r->res_lvbseq++;
2023 rsb_clear_flag(r, RSB_VALNOTVALID);
2024}
2025
2026/* lkb is process copy (pc) */
2027
2028static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
2029 struct dlm_message *ms)
2030{
2031 int b;
2032
2033 if (!lkb->lkb_lvbptr)
2034 return;
2035
2036 if (!(lkb->lkb_exflags & DLM_LKF_VALBLK))
2037 return;
2038
597d0cae 2039 b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1];
e7fd4179
DT		 2040 if (b == 1) {
2041 int len = receive_extralen(ms);
cfa805f6
BVA		 2042 if (len > r->res_ls->ls_lvblen)
2043 len = r->res_ls->ls_lvblen;
e7fd4179
DT		 2044 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
2045 lkb->lkb_lvbseq = ms->m_lvbseq;
2046 }
2047}
2048
2049/* Manipulate lkb's on rsb's convert/granted/waiting queues
2050 remove_lock -- used for unlock, removes lkb from granted
2051 revert_lock -- used for cancel, moves lkb from convert to granted
2052 grant_lock -- used for request and convert, adds lkb to granted or
2053 moves lkb from convert or waiting to granted
2054
2055 Each of these is used for master or local copy lkb's. There is
2056 also a _pc() variation used to make the corresponding change on
2057 a process copy (pc) lkb. */
2058
2059static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2060{
2061 del_lkb(r, lkb);
2062 lkb->lkb_grmode = DLM_LOCK_IV;
2063 /* this unhold undoes the original ref from create_lkb()
2064 so this leads to the lkb being freed */
2065 unhold_lkb(lkb);
2066}
2067
2068static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2069{
2070 set_lvb_unlock(r, lkb);
2071 _remove_lock(r, lkb);
2072}
2073
2074static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
2075{
2076 _remove_lock(r, lkb);
2077}
2078
ef0c2bb0
DT		 2079/* returns: 0 did nothing
2080 1 moved lock to granted
2081 -1 removed lock */
2082
2083static int revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 2084{
ef0c2bb0
DT		 2085 int rv = 0;
2086
e7fd4179
DT		 2087 lkb->lkb_rqmode = DLM_LOCK_IV;
2088
2089 switch (lkb->lkb_status) {
597d0cae
DT		 2090 case DLM_LKSTS_GRANTED:
2091 break;
e7fd4179
DT		 2092 case DLM_LKSTS_CONVERT:
2093 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
ef0c2bb0 2094 rv = 1;
e7fd4179
DT		 2095 break;
2096 case DLM_LKSTS_WAITING:
2097 del_lkb(r, lkb);
2098 lkb->lkb_grmode = DLM_LOCK_IV;
2099 /* this unhold undoes the original ref from create_lkb()
2100 so this leads to the lkb being freed */
2101 unhold_lkb(lkb);
ef0c2bb0 2102 rv = -1;
e7fd4179
DT		 2103 break;
2104 default:
2105 log_print("invalid status for revert %d", lkb->lkb_status);
2106 }
ef0c2bb0 2107 return rv;
e7fd4179
DT		 2108}
2109
ef0c2bb0 2110static int revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb)
e7fd4179 2111{
ef0c2bb0 2112 return revert_lock(r, lkb);
e7fd4179
DT		 2113}
2114
2115static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2116{
2117 if (lkb->lkb_grmode != lkb->lkb_rqmode) {
2118 lkb->lkb_grmode = lkb->lkb_rqmode;
2119 if (lkb->lkb_status)
2120 move_lkb(r, lkb, DLM_LKSTS_GRANTED);
2121 else
2122 add_lkb(r, lkb, DLM_LKSTS_GRANTED);
2123 }
2124
2125 lkb->lkb_rqmode = DLM_LOCK_IV;
4875647a 2126 lkb->lkb_highbast = 0;
e7fd4179
DT		 2127}
2128
2129static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
2130{
2131 set_lvb_lock(r, lkb);
2132 _grant_lock(r, lkb);
e7fd4179
DT		 2133}
2134
2135static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb,
2136 struct dlm_message *ms)
2137{
2138 set_lvb_lock_pc(r, lkb, ms);
2139 _grant_lock(r, lkb);
2140}
2141
2142/* called by grant_pending_locks() which means an async grant message must
2143 be sent to the requesting node in addition to granting the lock if the
2144 lkb belongs to a remote node. */
2145
2146static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb)
2147{
2148 grant_lock(r, lkb);
2149 if (is_master_copy(lkb))
2150 send_grant(r, lkb);
2151 else
2152 queue_cast(r, lkb, 0);
2153}
2154
7d3c1feb
DT		 2155/* The special CONVDEADLK, ALTPR and ALTCW flags allow the master to
2156 change the granted/requested modes. We're munging things accordingly in
2157 the process copy.
2158 CONVDEADLK: our grmode may have been forced down to NL to resolve a
2159 conversion deadlock
2160 ALTPR/ALTCW: our rqmode may have been changed to PR or CW to become
2161 compatible with other granted locks */
2162
2a7ce0ed 2163static void munge_demoted(struct dlm_lkb *lkb)
7d3c1feb 2164{
7d3c1feb
DT		 2165 if (lkb->lkb_rqmode == DLM_LOCK_IV || lkb->lkb_grmode == DLM_LOCK_IV) {
2166 log_print("munge_demoted %x invalid modes gr %d rq %d",
2167 lkb->lkb_id, lkb->lkb_grmode, lkb->lkb_rqmode);
2168 return;
2169 }
2170
2171 lkb->lkb_grmode = DLM_LOCK_NL;
2172}
2173
2174static void munge_altmode(struct dlm_lkb *lkb, struct dlm_message *ms)
2175{
2176 if (ms->m_type != DLM_MSG_REQUEST_REPLY &&
2177 ms->m_type != DLM_MSG_GRANT) {
2178 log_print("munge_altmode %x invalid reply type %d",
2179 lkb->lkb_id, ms->m_type);
2180 return;
2181 }
2182
2183 if (lkb->lkb_exflags & DLM_LKF_ALTPR)
2184 lkb->lkb_rqmode = DLM_LOCK_PR;
2185 else if (lkb->lkb_exflags & DLM_LKF_ALTCW)
2186 lkb->lkb_rqmode = DLM_LOCK_CW;
2187 else {
2188 log_print("munge_altmode invalid exflags %x", lkb->lkb_exflags);
2189 dlm_print_lkb(lkb);
2190 }
2191}
2192
e7fd4179
DT		 2193static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head)
2194{
2195 struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb,
2196 lkb_statequeue);
2197 if (lkb->lkb_id == first->lkb_id)
90135925 2198 return 1;
e7fd4179 2199
90135925 2200 return 0;
e7fd4179
DT		 2201}
2202
e7fd4179
DT		 2203/* Check if the given lkb conflicts with another lkb on the queue. */
2204
2205static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb)
2206{
2207 struct dlm_lkb *this;
2208
2209 list_for_each_entry(this, head, lkb_statequeue) {
2210 if (this == lkb)
2211 continue;
3bcd3687 2212 if (!modes_compat(this, lkb))
90135925 2213 return 1;
e7fd4179 2214 }
90135925 2215 return 0;
e7fd4179
DT		 2216}
2217
2218/*
2219 * "A conversion deadlock arises with a pair of lock requests in the converting
2220 * queue for one resource. The granted mode of each lock blocks the requested
2221 * mode of the other lock."
2222 *
c85d65e9
DT		 2223 * Part 2: if the granted mode of lkb is preventing an earlier lkb in the
2224 * convert queue from being granted, then deadlk/demote lkb.
e7fd4179
DT		 2225 *
2226 * Example:
2227 * Granted Queue: empty
2228 * Convert Queue: NL->EX (first lock)
2229 * PR->EX (second lock)
2230 *
2231 * The first lock can't be granted because of the granted mode of the second
2232 * lock and the second lock can't be granted because it's not first in the
c85d65e9
DT		 2233 * list. We either cancel lkb's conversion (PR->EX) and return EDEADLK, or we
2234 * demote the granted mode of lkb (from PR to NL) if it has the CONVDEADLK
2235 * flag set and return DEMOTED in the lksb flags.
e7fd4179 2236 *
c85d65e9
DT		 2237 * Originally, this function detected conv-deadlk in a more limited scope:
2238 * - if !modes_compat(lkb1, lkb2) && !modes_compat(lkb2, lkb1), or
2239 * - if lkb1 was the first entry in the queue (not just earlier), and was
2240 * blocked by the granted mode of lkb2, and there was nothing on the
2241 * granted queue preventing lkb1 from being granted immediately, i.e.
2242 * lkb2 was the only thing preventing lkb1 from being granted.
2243 *
2244 * That second condition meant we'd only say there was conv-deadlk if
2245 * resolving it (by demotion) would lead to the first lock on the convert
2246 * queue being granted right away. It allowed conversion deadlocks to exist
2247 * between locks on the convert queue while they couldn't be granted anyway.
2248 *
2249 * Now, we detect and take action on conversion deadlocks immediately when
2250 * they're created, even if they may not be immediately consequential. If
2251 * lkb1 exists anywhere in the convert queue and lkb2 comes in with a granted
2252 * mode that would prevent lkb1's conversion from being granted, we do a
2253 * deadlk/demote on lkb2 right away and don't let it onto the convert queue.
2254 * I think this means that the lkb_is_ahead condition below should always
2255 * be zero, i.e. there will never be conv-deadlk between two locks that are
2256 * both already on the convert queue.
e7fd4179
DT		 2257 */
2258
c85d65e9 2259static int conversion_deadlock_detect(struct dlm_rsb *r, struct dlm_lkb *lkb2)
e7fd4179 2260{
c85d65e9
DT		 2261 struct dlm_lkb *lkb1;
2262 int lkb_is_ahead = 0;
e7fd4179 2263
c85d65e9
DT		 2264 list_for_each_entry(lkb1, &r->res_convertqueue, lkb_statequeue) {
2265 if (lkb1 == lkb2) {
2266 lkb_is_ahead = 1;
e7fd4179
DT		 2267 continue;
2268 }
2269
c85d65e9
DT		 2270 if (!lkb_is_ahead) {
2271 if (!modes_compat(lkb2, lkb1))
2272 return 1;
2273 } else {
2274 if (!modes_compat(lkb2, lkb1) &&
2275 !modes_compat(lkb1, lkb2))
2276 return 1;
2277 }
e7fd4179 2278 }
90135925 2279 return 0;
e7fd4179
DT		 2280}
2281
2282/*
2283 * Return 1 if the lock can be granted, 0 otherwise.
2284 * Also detect and resolve conversion deadlocks.
2285 *
2286 * lkb is the lock to be granted
2287 *
2288 * now is 1 if the function is being called in the context of the
2289 * immediate request, it is 0 if called later, after the lock has been
2290 * queued.
2291 *
c503a621
DT		 2292 * recover is 1 if dlm_recover_grant() is trying to grant conversions
2293 * after recovery.
2294 *
e7fd4179
DT		 2295 * References are from chapter 6 of "VAXcluster Principles" by Roy Davis
2296 */
2297
c503a621
DT		 2298static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
2299 int recover)
e7fd4179
DT		 2300{
2301 int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV);
2302
2303 /*
2304 * 6-10: Version 5.4 introduced an option to address the phenomenon of
2305 * a new request for a NL mode lock being blocked.
2306 *
2307 * 6-11: If the optional EXPEDITE flag is used with the new NL mode
2308 * request, then it would be granted. In essence, the use of this flag
2309 * tells the Lock Manager to expedite theis request by not considering
2310 * what may be in the CONVERTING or WAITING queues... As of this
2311 * writing, the EXPEDITE flag can be used only with new requests for NL
2312 * mode locks. This flag is not valid for conversion requests.
2313 *
2314 * A shortcut. Earlier checks return an error if EXPEDITE is used in a
2315 * conversion or used with a non-NL requested mode. We also know an
2316 * EXPEDITE request is always granted immediately, so now must always
2317 * be 1. The full condition to grant an expedite request: (now &&
2318 * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can
2319 * therefore be shortened to just checking the flag.
2320 */
2321
2322 if (lkb->lkb_exflags & DLM_LKF_EXPEDITE)
90135925 2323 return 1;
e7fd4179
DT		 2324
2325 /*
2326 * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be
2327 * added to the remaining conditions.
2328 */
2329
2330 if (queue_conflict(&r->res_grantqueue, lkb))
c503a621 2331 return 0;
e7fd4179
DT		 2332
2333 /*
2334 * 6-3: By default, a conversion request is immediately granted if the
2335 * requested mode is compatible with the modes of all other granted
2336 * locks
2337 */
2338
2339 if (queue_conflict(&r->res_convertqueue, lkb))
c503a621
DT		 2340 return 0;
2341
2342 /*
2343 * The RECOVER_GRANT flag means dlm_recover_grant() is granting
2344 * locks for a recovered rsb, on which lkb's have been rebuilt.
2345 * The lkb's may have been rebuilt on the queues in a different
2346 * order than they were in on the previous master. So, granting
2347 * queued conversions in order after recovery doesn't make sense
2348 * since the order hasn't been preserved anyway. The new order
2349 * could also have created a new "in place" conversion deadlock.
2350 * (e.g. old, failed master held granted EX, with PR->EX, NL->EX.
2351 * After recovery, there would be no granted locks, and possibly
2352 * NL->EX, PR->EX, an in-place conversion deadlock.) So, after
2353 * recovery, grant conversions without considering order.
2354 */
2355
2356 if (conv && recover)
2357 return 1;
e7fd4179
DT		 2358
2359 /*
2360 * 6-5: But the default algorithm for deciding whether to grant or
2361 * queue conversion requests does not by itself guarantee that such
2362 * requests are serviced on a "first come first serve" basis. This, in
2363 * turn, can lead to a phenomenon known as "indefinate postponement".
2364 *
2365 * 6-7: This issue is dealt with by using the optional QUECVT flag with
2366 * the system service employed to request a lock conversion. This flag
2367 * forces certain conversion requests to be queued, even if they are
2368 * compatible with the granted modes of other locks on the same
2369 * resource. Thus, the use of this flag results in conversion requests
2370 * being ordered on a "first come first servce" basis.
2371 *
2372 * DCT: This condition is all about new conversions being able to occur
2373 * "in place" while the lock remains on the granted queue (assuming
2374 * nothing else conflicts.) IOW if QUECVT isn't set, a conversion
2375 * doesn't _have_ to go onto the convert queue where it's processed in
2376 * order. The "now" variable is necessary to distinguish converts
2377 * being received and processed for the first time now, because once a
2378 * convert is moved to the conversion queue the condition below applies
2379 * requiring fifo granting.
2380 */
2381
2382 if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT))
90135925 2383 return 1;
e7fd4179 2384
53ad1c98
DT		 2385 /*
2386 * Even if the convert is compat with all granted locks,
2387 * QUECVT forces it behind other locks on the convert queue.
2388 */
2389
2390 if (now && conv && (lkb->lkb_exflags & DLM_LKF_QUECVT)) {
2391 if (list_empty(&r->res_convertqueue))
2392 return 1;
2393 else
c503a621 2394 return 0;
53ad1c98
DT		 2395 }
2396
e7fd4179 2397 /*
3bcd3687
DT		 2398 * The NOORDER flag is set to avoid the standard vms rules on grant
2399 * order.
e7fd4179
DT		 2400 */
2401
2402 if (lkb->lkb_exflags & DLM_LKF_NOORDER)
90135925 2403 return 1;
e7fd4179
DT		 2404
2405 /*
2406 * 6-3: Once in that queue [CONVERTING], a conversion request cannot be
2407 * granted until all other conversion requests ahead of it are granted
2408 * and/or canceled.
2409 */
2410
2411 if (!now && conv && first_in_list(lkb, &r->res_convertqueue))
90135925 2412 return 1;
e7fd4179
DT		 2413
2414 /*
2415 * 6-4: By default, a new request is immediately granted only if all
2416 * three of the following conditions are satisfied when the request is
2417 * issued:
2418 * - The queue of ungranted conversion requests for the resource is
2419 * empty.
2420 * - The queue of ungranted new requests for the resource is empty.
2421 * - The mode of the new request is compatible with the most
2422 * restrictive mode of all granted locks on the resource.
2423 */
2424
2425 if (now && !conv && list_empty(&r->res_convertqueue) &&
2426 list_empty(&r->res_waitqueue))
90135925 2427 return 1;
e7fd4179
DT		 2428
2429 /*
2430 * 6-4: Once a lock request is in the queue of ungranted new requests,
2431 * it cannot be granted until the queue of ungranted conversion
2432 * requests is empty, all ungranted new requests ahead of it are
2433 * granted and/or canceled, and it is compatible with the granted mode
2434 * of the most restrictive lock granted on the resource.
2435 */
2436
2437 if (!now && !conv && list_empty(&r->res_convertqueue) &&
2438 first_in_list(lkb, &r->res_waitqueue))
90135925 2439 return 1;
c503a621 2440
90135925 2441 return 0;
e7fd4179
DT		 2442}
2443
c85d65e9 2444static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now,
c503a621 2445 int recover, int *err)
e7fd4179 2446{
e7fd4179
DT		 2447 int rv;
2448 int8_t alt = 0, rqmode = lkb->lkb_rqmode;
c85d65e9
DT		 2449 int8_t is_convert = (lkb->lkb_grmode != DLM_LOCK_IV);
2450
2451 if (err)
2452 *err = 0;
e7fd4179 2453
c503a621 2454 rv = _can_be_granted(r, lkb, now, recover);
e7fd4179
DT		 2455 if (rv)
2456 goto out;
2457
c85d65e9
DT		 2458 /*
2459 * The CONVDEADLK flag is non-standard and tells the dlm to resolve
2460 * conversion deadlocks by demoting grmode to NL, otherwise the dlm
2461 * cancels one of the locks.
2462 */
2463
2464 if (is_convert && can_be_queued(lkb) &&
2465 conversion_deadlock_detect(r, lkb)) {
2466 if (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) {
2467 lkb->lkb_grmode = DLM_LOCK_NL;
2468 lkb->lkb_sbflags |= DLM_SBF_DEMOTED;
2469 } else if (!(lkb->lkb_exflags & DLM_LKF_NODLCKWT)) {
2470 if (err)
2471 *err = -EDEADLK;
2472 else {
2473 log_print("can_be_granted deadlock %x now %d",
2474 lkb->lkb_id, now);
2475 dlm_dump_rsb(r);
2476 }
2477 }
e7fd4179 2478 goto out;
c85d65e9 2479 }
e7fd4179 2480
c85d65e9
DT		 2481 /*
2482 * The ALTPR and ALTCW flags are non-standard and tell the dlm to try
2483 * to grant a request in a mode other than the normal rqmode. It's a
2484 * simple way to provide a big optimization to applications that can
2485 * use them.
2486 */
2487
2488 if (rqmode != DLM_LOCK_PR && (lkb->lkb_exflags & DLM_LKF_ALTPR))
e7fd4179 2489 alt = DLM_LOCK_PR;
c85d65e9 2490 else if (rqmode != DLM_LOCK_CW && (lkb->lkb_exflags & DLM_LKF_ALTCW))
e7fd4179
DT		 2491 alt = DLM_LOCK_CW;
2492
2493 if (alt) {
2494 lkb->lkb_rqmode = alt;
c503a621 2495 rv = _can_be_granted(r, lkb, now, 0);
e7fd4179
DT		 2496 if (rv)
2497 lkb->lkb_sbflags |= DLM_SBF_ALTMODE;
2498 else
2499 lkb->lkb_rqmode = rqmode;
2500 }
2501 out:
2502 return rv;
2503}
2504
c85d65e9
DT		 2505/* FIXME: I don't think that can_be_granted() can/will demote or find deadlock
2506 for locks pending on the convert list. Once verified (watch for these
2507 log_prints), we should be able to just call _can_be_granted() and not
2508 bother with the demote/deadlk cases here (and there's no easy way to deal
2509 with a deadlk here, we'd have to generate something like grant_lock with
2510 the deadlk error.) */
2511
36509258
DT		 2512/* Returns the highest requested mode of all blocked conversions; sets
2513 cw if there's a blocked conversion to DLM_LOCK_CW. */
c85d65e9 2514
4875647a
DT		 2515static int grant_pending_convert(struct dlm_rsb *r, int high, int *cw,
2516 unsigned int *count)
e7fd4179
DT		 2517{
2518 struct dlm_lkb *lkb, *s;
c503a621 2519 int recover = rsb_flag(r, RSB_RECOVER_GRANT);
e7fd4179 2520 int hi, demoted, quit, grant_restart, demote_restart;
c85d65e9 2521 int deadlk;
e7fd4179
DT		 2522
2523 quit = 0;
2524 restart:
2525 grant_restart = 0;
2526 demote_restart = 0;
2527 hi = DLM_LOCK_IV;
2528
2529 list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) {
2530 demoted = is_demoted(lkb);
c85d65e9
DT		 2531 deadlk = 0;
2532
c503a621 2533 if (can_be_granted(r, lkb, 0, recover, &deadlk)) {
e7fd4179
DT		 2534 grant_lock_pending(r, lkb);
2535 grant_restart = 1;
4875647a
DT		 2536 if (count)
2537 (*count)++;
c85d65e9 2538 continue;
e7fd4179 2539 }
c85d65e9
DT		 2540
2541 if (!demoted && is_demoted(lkb)) {
2542 log_print("WARN: pending demoted %x node %d %s",
2543 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
2544 demote_restart = 1;
2545 continue;
2546 }
2547
2548 if (deadlk) {
2549 log_print("WARN: pending deadlock %x node %d %s",
2550 lkb->lkb_id, lkb->lkb_nodeid, r->res_name);
2551 dlm_dump_rsb(r);
2552 continue;
2553 }
2554
2555 hi = max_t(int, lkb->lkb_rqmode, hi);
36509258
DT		 2556
2557 if (cw && lkb->lkb_rqmode == DLM_LOCK_CW)
2558 *cw = 1;
e7fd4179
DT		 2559 }
2560
2561 if (grant_restart)
2562 goto restart;
2563 if (demote_restart && !quit) {
2564 quit = 1;
2565 goto restart;
2566 }
2567
2568 return max_t(int, high, hi);
2569}
2570
4875647a
DT		 2571static int grant_pending_wait(struct dlm_rsb *r, int high, int *cw,
2572 unsigned int *count)
e7fd4179
DT		 2573{
2574 struct dlm_lkb *lkb, *s;
2575
2576 list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) {
c503a621 2577 if (can_be_granted(r, lkb, 0, 0, NULL)) {
e7fd4179 2578 grant_lock_pending(r, lkb);
4875647a
DT		 2579 if (count)
2580 (*count)++;
2581 } else {
e7fd4179 2582 high = max_t(int, lkb->lkb_rqmode, high);
36509258
DT		 2583 if (lkb->lkb_rqmode == DLM_LOCK_CW)
2584 *cw = 1;
2585 }
e7fd4179
DT		 2586 }
2587
2588 return high;
2589}
2590
36509258
DT		 2591/* cw of 1 means there's a lock with a rqmode of DLM_LOCK_CW that's blocked
2592 on either the convert or waiting queue.
2593 high is the largest rqmode of all locks blocked on the convert or
2594 waiting queue. */
2595
2596static int lock_requires_bast(struct dlm_lkb *gr, int high, int cw)
2597{
2598 if (gr->lkb_grmode == DLM_LOCK_PR && cw) {
2599 if (gr->lkb_highbast < DLM_LOCK_EX)
2600 return 1;
2601 return 0;
2602 }
2603
2604 if (gr->lkb_highbast < high &&
2605 !__dlm_compat_matrix[gr->lkb_grmode+1][high+1])
2606 return 1;
2607 return 0;
2608}
2609
4875647a 2610static void grant_pending_locks(struct dlm_rsb *r, unsigned int *count)
e7fd4179
DT		 2611{
2612 struct dlm_lkb *lkb, *s;
2613 int high = DLM_LOCK_IV;
36509258 2614 int cw = 0;
e7fd4179 2615
4875647a
DT		 2616 if (!is_master(r)) {
2617 log_print("grant_pending_locks r nodeid %d", r->res_nodeid);
2618 dlm_dump_rsb(r);
2619 return;
2620 }
e7fd4179 2621
4875647a
DT		 2622 high = grant_pending_convert(r, high, &cw, count);
2623 high = grant_pending_wait(r, high, &cw, count);
e7fd4179
DT		 2624
2625 if (high == DLM_LOCK_IV)
2626 return;
2627
2628 /*
2629 * If there are locks left on the wait/convert queue then send blocking
2630 * ASTs to granted locks based on the largest requested mode (high)
36509258 2631 * found above.
e7fd4179
DT		 2632 */
2633
2634 list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) {
e5dae548 2635 if (lkb->lkb_bastfn && lock_requires_bast(lkb, high, cw)) {
329fc4c3
DT		 2636 if (cw && high == DLM_LOCK_PR &&
2637 lkb->lkb_grmode == DLM_LOCK_PR)
36509258
DT		 2638 queue_bast(r, lkb, DLM_LOCK_CW);
2639 else
2640 queue_bast(r, lkb, high);
e7fd4179
DT		 2641 lkb->lkb_highbast = high;
2642 }
2643 }
2644}
2645
36509258
DT		 2646static int modes_require_bast(struct dlm_lkb *gr, struct dlm_lkb *rq)
2647{
2648 if ((gr->lkb_grmode == DLM_LOCK_PR && rq->lkb_rqmode == DLM_LOCK_CW) ||
2649 (gr->lkb_grmode == DLM_LOCK_CW && rq->lkb_rqmode == DLM_LOCK_PR)) {
2650 if (gr->lkb_highbast < DLM_LOCK_EX)
2651 return 1;
2652 return 0;
2653 }
2654
2655 if (gr->lkb_highbast < rq->lkb_rqmode && !modes_compat(gr, rq))
2656 return 1;
2657 return 0;
2658}
2659
e7fd4179
DT		 2660static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
2661 struct dlm_lkb *lkb)
2662{
2663 struct dlm_lkb *gr;
2664
2665 list_for_each_entry(gr, head, lkb_statequeue) {
314dd2a0
SW		 2666 /* skip self when sending basts to convertqueue */
2667 if (gr == lkb)
2668 continue;
e5dae548 2669 if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
e7fd4179
DT		 2670 queue_bast(r, gr, lkb->lkb_rqmode);
2671 gr->lkb_highbast = lkb->lkb_rqmode;
2672 }
2673 }
2674}
2675
2676static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb)
2677{
2678 send_bast_queue(r, &r->res_grantqueue, lkb);
2679}
2680
2681static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb)
2682{
2683 send_bast_queue(r, &r->res_grantqueue, lkb);
2684 send_bast_queue(r, &r->res_convertqueue, lkb);
2685}
2686
2687/* set_master(r, lkb) -- set the master nodeid of a resource
2688
2689 The purpose of this function is to set the nodeid field in the given
2690 lkb using the nodeid field in the given rsb. If the rsb's nodeid is
2691 known, it can just be copied to the lkb and the function will return
2692 0. If the rsb's nodeid is _not_ known, it needs to be looked up
2693 before it can be copied to the lkb.
2694
2695 When the rsb nodeid is being looked up remotely, the initial lkb
2696 causing the lookup is kept on the ls_waiters list waiting for the
2697 lookup reply. Other lkb's waiting for the same rsb lookup are kept
2698 on the rsb's res_lookup list until the master is verified.
2699
2700 Return values:
2701 0: nodeid is set in rsb/lkb and the caller should go ahead and use it
2702 1: the rsb master is not available and the lkb has been placed on
2703 a wait queue
2704*/
2705
2706static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb)
2707{
c04fecb4 2708 int our_nodeid = dlm_our_nodeid();
e7fd4179
DT		 2709
2710 if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) {
2711 rsb_clear_flag(r, RSB_MASTER_UNCERTAIN);
2712 r->res_first_lkid = lkb->lkb_id;
2713 lkb->lkb_nodeid = r->res_nodeid;
2714 return 0;
2715 }
2716
2717 if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) {
2718 list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup);
2719 return 1;
2720 }
2721
c04fecb4 2722 if (r->res_master_nodeid == our_nodeid) {
e7fd4179
DT		 2723 lkb->lkb_nodeid = 0;
2724 return 0;
2725 }
2726
c04fecb4
DT		 2727 if (r->res_master_nodeid) {
2728 lkb->lkb_nodeid = r->res_master_nodeid;
e7fd4179
DT		 2729 return 0;
2730 }
2731
c04fecb4
DT		 2732 if (dlm_dir_nodeid(r) == our_nodeid) {
2733 /* This is a somewhat unusual case; find_rsb will usually
2734 have set res_master_nodeid when dir nodeid is local, but
2735 there are cases where we become the dir node after we've
2736 past find_rsb and go through _request_lock again.
2737 confirm_master() or process_lookup_list() needs to be
2738 called after this. */
2739 log_debug(r->res_ls, "set_master %x self master %d dir %d %s",
2740 lkb->lkb_id, r->res_master_nodeid, r->res_dir_nodeid,
2741 r->res_name);
2742 r->res_master_nodeid = our_nodeid;
e7fd4179
DT		 2743 r->res_nodeid = 0;
2744 lkb->lkb_nodeid = 0;
c04fecb4 2745 return 0;
e7fd4179 2746 }
c04fecb4 2747
05c32f47
DT		 2748 wait_pending_remove(r);
2749
c04fecb4
DT		 2750 r->res_first_lkid = lkb->lkb_id;
2751 send_lookup(r, lkb);
2752 return 1;
e7fd4179
DT		 2753}
2754
2755static void process_lookup_list(struct dlm_rsb *r)
2756{
2757 struct dlm_lkb *lkb, *safe;
2758
2759 list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) {
ef0c2bb0 2760 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 2761 _request_lock(r, lkb);
2762 schedule();
2763 }
2764}
2765
2766/* confirm_master -- confirm (or deny) an rsb's master nodeid */
2767
2768static void confirm_master(struct dlm_rsb *r, int error)
2769{
2770 struct dlm_lkb *lkb;
2771
2772 if (!r->res_first_lkid)
2773 return;
2774
2775 switch (error) {
2776 case 0:
2777 case -EINPROGRESS:
2778 r->res_first_lkid = 0;
2779 process_lookup_list(r);
2780 break;
2781
2782 case -EAGAIN:
aec64e1b
DT		 2783 case -EBADR:
2784 case -ENOTBLK:
2785 /* the remote request failed and won't be retried (it was
2786 a NOQUEUE, or has been canceled/unlocked); make a waiting
2787 lkb the first_lkid */
e7fd4179
DT		 2788
2789 r->res_first_lkid = 0;
2790
2791 if (!list_empty(&r->res_lookup)) {
2792 lkb = list_entry(r->res_lookup.next, struct dlm_lkb,
2793 lkb_rsb_lookup);
ef0c2bb0 2794 list_del_init(&lkb->lkb_rsb_lookup);
e7fd4179
DT		 2795 r->res_first_lkid = lkb->lkb_id;
2796 _request_lock(r, lkb);
761b9d3f 2797 }
e7fd4179
DT		 2798 break;
2799
2800 default:
2801 log_error(r->res_ls, "confirm_master unknown error %d", error);
2802 }
2803}
2804
2805static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags,
e5dae548
DT		 2806 int namelen, unsigned long timeout_cs,
2807 void (*ast) (void *astparam),
2808 void *astparam,
2809 void (*bast) (void *astparam, int mode),
2810 struct dlm_args *args)
e7fd4179
DT		 2811{
2812 int rv = -EINVAL;
2813
2814 /* check for invalid arg usage */
2815
2816 if (mode < 0 || mode > DLM_LOCK_EX)
2817 goto out;
2818
2819 if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN))
2820 goto out;
2821
2822 if (flags & DLM_LKF_CANCEL)
2823 goto out;
2824
2825 if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT))
2826 goto out;
2827
2828 if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT))
2829 goto out;
2830
2831 if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE)
2832 goto out;
2833
2834 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT)
2835 goto out;
2836
2837 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT)
2838 goto out;
2839
2840 if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE)
2841 goto out;
2842
2843 if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL)
2844 goto out;
2845
2846 if (!ast || !lksb)
2847 goto out;
2848
2849 if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr)
2850 goto out;
2851
e7fd4179
DT		 2852 if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid)
2853 goto out;
2854
2855 /* these args will be copied to the lkb in validate_lock_args,
2856 it cannot be done now because when converting locks, fields in
2857 an active lkb cannot be modified before locking the rsb */
2858
2859 args->flags = flags;
e5dae548
DT		 2860 args->astfn = ast;
2861 args->astparam = astparam;
2862 args->bastfn = bast;
d7db923e 2863 args->timeout = timeout_cs;
e7fd4179
DT		 2864 args->mode = mode;
2865 args->lksb = lksb;
e7fd4179
DT		 2866 rv = 0;
2867 out:
2868 return rv;
2869}
2870
2871static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
2872{
2873 if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK |
2874 DLM_LKF_FORCEUNLOCK))
2875 return -EINVAL;
2876
ef0c2bb0
DT		 2877 if (flags & DLM_LKF_CANCEL && flags & DLM_LKF_FORCEUNLOCK)
2878 return -EINVAL;
2879
e7fd4179 2880 args->flags = flags;
e5dae548 2881 args->astparam = astarg;
e7fd4179
DT		 2882 return 0;
2883}
2884
2885static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
2886 struct dlm_args *args)
2887{
2888 int rv = -EINVAL;
2889
2890 if (args->flags & DLM_LKF_CONVERT) {
2891 if (lkb->lkb_flags & DLM_IFL_MSTCPY)
2892 goto out;
2893
2894 if (args->flags & DLM_LKF_QUECVT &&
2895 !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
2896 goto out;
2897
2898 rv = -EBUSY;
2899 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
2900 goto out;
2901
2902 if (lkb->lkb_wait_type)
2903 goto out;
ef0c2bb0
DT		 2904
2905 if (is_overlap(lkb))
2906 goto out;
e7fd4179
DT		 2907 }
2908
2909 lkb->lkb_exflags = args->flags;
2910 lkb->lkb_sbflags = 0;
e5dae548 2911 lkb->lkb_astfn = args->astfn;
e7fd4179 2912 lkb->lkb_astparam = args->astparam;
e5dae548 2913 lkb->lkb_bastfn = args->bastfn;
e7fd4179
DT		 2914 lkb->lkb_rqmode = args->mode;
2915 lkb->lkb_lksb = args->lksb;
2916 lkb->lkb_lvbptr = args->lksb->sb_lvbptr;
2917 lkb->lkb_ownpid = (int) current->pid;
d7db923e 2918 lkb->lkb_timeout_cs = args->timeout;
e7fd4179
DT		 2919 rv = 0;
2920 out:
43279e53
DT		 2921 if (rv)
2922 log_debug(ls, "validate_lock_args %d %x %x %x %d %d %s",
2923 rv, lkb->lkb_id, lkb->lkb_flags, args->flags,
2924 lkb->lkb_status, lkb->lkb_wait_type,
2925 lkb->lkb_resource->res_name);
e7fd4179
DT		 2926 return rv;
2927}
2928
ef0c2bb0
DT		 2929/* when dlm_unlock() sees -EBUSY with CANCEL/FORCEUNLOCK it returns 0
2930 for success */
2931
2932/* note: it's valid for lkb_nodeid/res_nodeid to be -1 when we get here
2933 because there may be a lookup in progress and it's valid to do
2934 cancel/unlockf on it */
2935
e7fd4179
DT		 2936static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
2937{
ef0c2bb0 2938 struct dlm_ls *ls = lkb->lkb_resource->res_ls;
e7fd4179
DT		 2939 int rv = -EINVAL;
2940
ef0c2bb0
DT		 2941 if (lkb->lkb_flags & DLM_IFL_MSTCPY) {
2942 log_error(ls, "unlock on MSTCPY %x", lkb->lkb_id);
2943 dlm_print_lkb(lkb);
e7fd4179 2944 goto out;
ef0c2bb0 2945 }
e7fd4179 2946
ef0c2bb0
DT		 2947 /* an lkb may still exist even though the lock is EOL'ed due to a
2948 cancel, unlock or failed noqueue request; an app can't use these
2949 locks; return same error as if the lkid had not been found at all */
e7fd4179 2950
ef0c2bb0
DT		 2951 if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
2952 log_debug(ls, "unlock on ENDOFLIFE %x", lkb->lkb_id);
2953 rv = -ENOENT;
e7fd4179 2954 goto out;
ef0c2bb0 2955 }
e7fd4179 2956
ef0c2bb0
DT		 2957 /* an lkb may be waiting for an rsb lookup to complete where the
2958 lookup was initiated by another lock */
2959
42dc1601
DT		 2960 if (!list_empty(&lkb->lkb_rsb_lookup)) {
2961 if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
ef0c2bb0
DT		 2962 log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
2963 list_del_init(&lkb->lkb_rsb_lookup);
2964 queue_cast(lkb->lkb_resource, lkb,
2965 args->flags & DLM_LKF_CANCEL ?
2966 -DLM_ECANCEL : -DLM_EUNLOCK);
2967 unhold_lkb(lkb); /* undoes create_lkb() */
ef0c2bb0 2968 }
42dc1601
DT		 2969 /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
2970 rv = -EBUSY;
2971 goto out;
ef0c2bb0
DT		 2972 }
2973
2974 /* cancel not allowed with another cancel/unlock in progress */
2975
2976 if (args->flags & DLM_LKF_CANCEL) {
2977 if (lkb->lkb_exflags & DLM_LKF_CANCEL)
2978 goto out;
2979
2980 if (is_overlap(lkb))
2981 goto out;
2982
3ae1acf9
DT		 2983 /* don't let scand try to do a cancel */
2984 del_timeout(lkb);
2985
ef0c2bb0
DT		 2986 if (lkb->lkb_flags & DLM_IFL_RESEND) {
2987 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
2988 rv = -EBUSY;
2989 goto out;
2990 }
2991
a536e381
DT		 2992 /* there's nothing to cancel */
2993 if (lkb->lkb_status == DLM_LKSTS_GRANTED &&
2994 !lkb->lkb_wait_type) {
2995 rv = -EBUSY;
2996 goto out;
2997 }
2998
ef0c2bb0
DT		 2999 switch (lkb->lkb_wait_type) {
3000 case DLM_MSG_LOOKUP:
3001 case DLM_MSG_REQUEST:
3002 lkb->lkb_flags |= DLM_IFL_OVERLAP_CANCEL;
3003 rv = -EBUSY;
3004 goto out;
3005 case DLM_MSG_UNLOCK:
3006 case DLM_MSG_CANCEL:
3007 goto out;
3008 }
3009 /* add_to_waiters() will set OVERLAP_CANCEL */
3010 goto out_ok;
3011 }
3012
3013 /* do we need to allow a force-unlock if there's a normal unlock
3014 already in progress? in what conditions could the normal unlock
3015 fail such that we'd want to send a force-unlock to be sure? */
3016
3017 if (args->flags & DLM_LKF_FORCEUNLOCK) {
3018 if (lkb->lkb_exflags & DLM_LKF_FORCEUNLOCK)
3019 goto out;
3020
3021 if (is_overlap_unlock(lkb))
3022 goto out;
e7fd4179 3023
3ae1acf9
DT		 3024 /* don't let scand try to do a cancel */
3025 del_timeout(lkb);
3026
ef0c2bb0
DT		 3027 if (lkb->lkb_flags & DLM_IFL_RESEND) {
3028 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
3029 rv = -EBUSY;
3030 goto out;
3031 }
3032
3033 switch (lkb->lkb_wait_type) {
3034 case DLM_MSG_LOOKUP:
3035 case DLM_MSG_REQUEST:
3036 lkb->lkb_flags |= DLM_IFL_OVERLAP_UNLOCK;
3037 rv = -EBUSY;
3038 goto out;
3039 case DLM_MSG_UNLOCK:
3040 goto out;
3041 }
3042 /* add_to_waiters() will set OVERLAP_UNLOCK */
3043 goto out_ok;
3044 }
3045
3046 /* normal unlock not allowed if there's any op in progress */
e7fd4179 3047 rv = -EBUSY;
ef0c2bb0 3048 if (lkb->lkb_wait_type || lkb->lkb_wait_count)
e7fd4179
DT		 3049 goto out;
3050
3051 out_ok:
ef0c2bb0
DT		 3052 /* an overlapping op shouldn't blow away exflags from other op */
3053 lkb->lkb_exflags |= args->flags;
e7fd4179
DT		 3054 lkb->lkb_sbflags = 0;
3055 lkb->lkb_astparam = args->astparam;
e7fd4179
DT		 3056 rv = 0;
3057 out:
ef0c2bb0
DT		 3058 if (rv)
3059 log_debug(ls, "validate_unlock_args %d %x %x %x %x %d %s", rv,
3060 lkb->lkb_id, lkb->lkb_flags, lkb->lkb_exflags,
3061 args->flags, lkb->lkb_wait_type,
3062 lkb->lkb_resource->res_name);
e7fd4179
DT		 3063 return rv;
3064}
3065
3066/*
3067 * Four stage 4 varieties:
3068 * do_request(), do_convert(), do_unlock(), do_cancel()
3069 * These are called on the master node for the given lock and
3070 * from the central locking logic.
3071 */
3072
3073static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3074{
3075 int error = 0;
3076
c503a621 3077 if (can_be_granted(r, lkb, 1, 0, NULL)) {
e7fd4179
DT		 3078 grant_lock(r, lkb);
3079 queue_cast(r, lkb, 0);
3080 goto out;
3081 }
3082
3083 if (can_be_queued(lkb)) {
3084 error = -EINPROGRESS;
3085 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3ae1acf9 3086 add_timeout(lkb);
e7fd4179
DT		 3087 goto out;
3088 }
3089
3090 error = -EAGAIN;
e7fd4179 3091 queue_cast(r, lkb, -EAGAIN);
e7fd4179
DT		 3092 out:
3093 return error;
3094}
3095
cf6620ac
DT		 3096static void do_request_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3097 int error)
3098{
3099 switch (error) {
3100 case -EAGAIN:
3101 if (force_blocking_asts(lkb))
3102 send_blocking_asts_all(r, lkb);
3103 break;
3104 case -EINPROGRESS:
3105 send_blocking_asts(r, lkb);
3106 break;
3107 }
3108}
3109
e7fd4179
DT		 3110static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3111{
3112 int error = 0;
c85d65e9 3113 int deadlk = 0;
e7fd4179
DT		 3114
3115 /* changing an existing lock may allow others to be granted */
3116
c503a621 3117 if (can_be_granted(r, lkb, 1, 0, &deadlk)) {
e7fd4179
DT		 3118 grant_lock(r, lkb);
3119 queue_cast(r, lkb, 0);
e7fd4179
DT		 3120 goto out;
3121 }
3122
c85d65e9
DT		 3123 /* can_be_granted() detected that this lock would block in a conversion
3124 deadlock, so we leave it on the granted queue and return EDEADLK in
3125 the ast for the convert. */
3126
3127 if (deadlk) {
3128 /* it's left on the granted queue */
c85d65e9
DT		 3129 revert_lock(r, lkb);
3130 queue_cast(r, lkb, -EDEADLK);
3131 error = -EDEADLK;
3132 goto out;
3133 }
3134
7d3c1feb
DT		 3135 /* is_demoted() means the can_be_granted() above set the grmode
3136 to NL, and left us on the granted queue. This auto-demotion
3137 (due to CONVDEADLK) might mean other locks, and/or this lock, are
3138 now grantable. We have to try to grant other converting locks
3139 before we try again to grant this one. */
3140
3141 if (is_demoted(lkb)) {
4875647a 3142 grant_pending_convert(r, DLM_LOCK_IV, NULL, NULL);
c503a621 3143 if (_can_be_granted(r, lkb, 1, 0)) {
7d3c1feb
DT		 3144 grant_lock(r, lkb);
3145 queue_cast(r, lkb, 0);
7d3c1feb
DT		 3146 goto out;
3147 }
3148 /* else fall through and move to convert queue */
3149 }
3150
3151 if (can_be_queued(lkb)) {
e7fd4179
DT		 3152 error = -EINPROGRESS;
3153 del_lkb(r, lkb);
3154 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3ae1acf9 3155 add_timeout(lkb);
e7fd4179
DT		 3156 goto out;
3157 }
3158
3159 error = -EAGAIN;
e7fd4179 3160 queue_cast(r, lkb, -EAGAIN);
e7fd4179
DT		 3161 out:
3162 return error;
3163}
3164
cf6620ac
DT		 3165static void do_convert_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3166 int error)
3167{
3168 switch (error) {
3169 case 0:
4875647a 3170 grant_pending_locks(r, NULL);
cf6620ac
DT		 3171 /* grant_pending_locks also sends basts */
3172 break;
3173 case -EAGAIN:
3174 if (force_blocking_asts(lkb))
3175 send_blocking_asts_all(r, lkb);
3176 break;
3177 case -EINPROGRESS:
3178 send_blocking_asts(r, lkb);
3179 break;
3180 }
3181}
3182
e7fd4179
DT		 3183static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3184{
3185 remove_lock(r, lkb);
3186 queue_cast(r, lkb, -DLM_EUNLOCK);
e7fd4179
DT		 3187 return -DLM_EUNLOCK;
3188}
3189
cf6620ac
DT		 3190static void do_unlock_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3191 int error)
3192{
4875647a 3193 grant_pending_locks(r, NULL);
cf6620ac
DT		 3194}
3195
ef0c2bb0 3196/* returns: 0 did nothing, -DLM_ECANCEL canceled lock */
c04fecb4 3197
e7fd4179
DT		 3198static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3199{
ef0c2bb0
DT		 3200 int error;
3201
3202 error = revert_lock(r, lkb);
3203 if (error) {
3204 queue_cast(r, lkb, -DLM_ECANCEL);
ef0c2bb0
DT		 3205 return -DLM_ECANCEL;
3206 }
3207 return 0;
e7fd4179
DT		 3208}
3209
cf6620ac
DT		 3210static void do_cancel_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
3211 int error)
3212{
3213 if (error)
4875647a 3214 grant_pending_locks(r, NULL);
cf6620ac
DT		 3215}
3216
e7fd4179
DT		 3217/*
3218 * Four stage 3 varieties:
3219 * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock()
3220 */
3221
3222/* add a new lkb to a possibly new rsb, called by requesting process */
3223
3224static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3225{
3226 int error;
3227
3228 /* set_master: sets lkb nodeid from r */
3229
3230 error = set_master(r, lkb);
3231 if (error < 0)
3232 goto out;
3233 if (error) {
3234 error = 0;
3235 goto out;
3236 }
3237
cf6620ac 3238 if (is_remote(r)) {
e7fd4179
DT		 3239 /* receive_request() calls do_request() on remote node */
3240 error = send_request(r, lkb);
cf6620ac 3241 } else {
e7fd4179 3242 error = do_request(r, lkb);
cf6620ac
DT		 3243 /* for remote locks the request_reply is sent
3244 between do_request and do_request_effects */
3245 do_request_effects(r, lkb, error);
3246 }
e7fd4179
DT		 3247 out:
3248 return error;
3249}
3250
3bcd3687 3251/* change some property of an existing lkb, e.g. mode */
e7fd4179
DT		 3252
3253static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3254{
3255 int error;
3256
cf6620ac 3257 if (is_remote(r)) {
e7fd4179
DT		 3258 /* receive_convert() calls do_convert() on remote node */
3259 error = send_convert(r, lkb);
cf6620ac 3260 } else {
e7fd4179 3261 error = do_convert(r, lkb);
cf6620ac
DT		 3262 /* for remote locks the convert_reply is sent
3263 between do_convert and do_convert_effects */
3264 do_convert_effects(r, lkb, error);
3265 }
e7fd4179
DT		 3266
3267 return error;
3268}
3269
3270/* remove an existing lkb from the granted queue */
3271
3272static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3273{
3274 int error;
3275
cf6620ac 3276 if (is_remote(r)) {
e7fd4179
DT		 3277 /* receive_unlock() calls do_unlock() on remote node */
3278 error = send_unlock(r, lkb);
cf6620ac 3279 } else {
e7fd4179 3280 error = do_unlock(r, lkb);
cf6620ac
DT		 3281 /* for remote locks the unlock_reply is sent
3282 between do_unlock and do_unlock_effects */
3283 do_unlock_effects(r, lkb, error);
3284 }
e7fd4179
DT		 3285
3286 return error;
3287}
3288
3289/* remove an existing lkb from the convert or wait queue */
3290
3291static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3292{
3293 int error;
3294
cf6620ac 3295 if (is_remote(r)) {
e7fd4179
DT		 3296 /* receive_cancel() calls do_cancel() on remote node */
3297 error = send_cancel(r, lkb);
cf6620ac 3298 } else {
e7fd4179 3299 error = do_cancel(r, lkb);
cf6620ac
DT		 3300 /* for remote locks the cancel_reply is sent
3301 between do_cancel and do_cancel_effects */
3302 do_cancel_effects(r, lkb, error);
3303 }
e7fd4179
DT		 3304
3305 return error;
3306}
3307
3308/*
3309 * Four stage 2 varieties:
3310 * request_lock(), convert_lock(), unlock_lock(), cancel_lock()
3311 */
3312
3313static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name,
3314 int len, struct dlm_args *args)
3315{
3316 struct dlm_rsb *r;
3317 int error;
3318
3319 error = validate_lock_args(ls, lkb, args);
3320 if (error)
c04fecb4 3321 return error;
e7fd4179 3322
c04fecb4 3323 error = find_rsb(ls, name, len, 0, R_REQUEST, &r);
e7fd4179 3324 if (error)
c04fecb4 3325 return error;
e7fd4179
DT		 3326
3327 lock_rsb(r);
3328
3329 attach_lkb(r, lkb);
3330 lkb->lkb_lksb->sb_lkid = lkb->lkb_id;
3331
3332 error = _request_lock(r, lkb);
3333
3334 unlock_rsb(r);
3335 put_rsb(r);
e7fd4179
DT		 3336 return error;
3337}
3338
3339static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3340 struct dlm_args *args)
3341{
3342 struct dlm_rsb *r;
3343 int error;
3344
3345 r = lkb->lkb_resource;
3346
3347 hold_rsb(r);
3348 lock_rsb(r);
3349
3350 error = validate_lock_args(ls, lkb, args);
3351 if (error)
3352 goto out;
3353
3354 error = _convert_lock(r, lkb);
3355 out:
3356 unlock_rsb(r);
3357 put_rsb(r);
3358 return error;
3359}
3360
3361static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3362 struct dlm_args *args)
3363{
3364 struct dlm_rsb *r;
3365 int error;
3366
3367 r = lkb->lkb_resource;
3368
3369 hold_rsb(r);
3370 lock_rsb(r);
3371
3372 error = validate_unlock_args(lkb, args);
3373 if (error)
3374 goto out;
3375
3376 error = _unlock_lock(r, lkb);
3377 out:
3378 unlock_rsb(r);
3379 put_rsb(r);
3380 return error;
3381}
3382
3383static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb,
3384 struct dlm_args *args)
3385{
3386 struct dlm_rsb *r;
3387 int error;
3388
3389 r = lkb->lkb_resource;
3390
3391 hold_rsb(r);
3392 lock_rsb(r);
3393
3394 error = validate_unlock_args(lkb, args);
3395 if (error)
3396 goto out;
3397
3398 error = _cancel_lock(r, lkb);
3399 out:
3400 unlock_rsb(r);
3401 put_rsb(r);
3402 return error;
3403}
3404
3405/*
3406 * Two stage 1 varieties: dlm_lock() and dlm_unlock()
3407 */
3408
3409int dlm_lock(dlm_lockspace_t *lockspace,
3410 int mode,
3411 struct dlm_lksb *lksb,
3412 uint32_t flags,
3413 void *name,
3414 unsigned int namelen,
3415 uint32_t parent_lkid,
3416 void (*ast) (void *astarg),
3417 void *astarg,
3bcd3687 3418 void (*bast) (void *astarg, int mode))
e7fd4179
DT		 3419{
3420 struct dlm_ls *ls;
3421 struct dlm_lkb *lkb;
3422 struct dlm_args args;
3423 int error, convert = flags & DLM_LKF_CONVERT;
3424
3425 ls = dlm_find_lockspace_local(lockspace);
3426 if (!ls)
3427 return -EINVAL;
3428
85e86edf 3429 dlm_lock_recovery(ls);
e7fd4179
DT		 3430
3431 if (convert)
3432 error = find_lkb(ls, lksb->sb_lkid, &lkb);
3433 else
3434 error = create_lkb(ls, &lkb);
3435
3436 if (error)
3437 goto out;
3438
d7db923e 3439 error = set_lock_args(mode, lksb, flags, namelen, 0, ast,
3bcd3687 3440 astarg, bast, &args);
e7fd4179
DT		 3441 if (error)
3442 goto out_put;
3443
3444 if (convert)
3445 error = convert_lock(ls, lkb, &args);
3446 else
3447 error = request_lock(ls, lkb, name, namelen, &args);
3448
3449 if (error == -EINPROGRESS)
3450 error = 0;
3451 out_put:
3452 if (convert || error)
b3f58d8f 3453 __put_lkb(ls, lkb);
c85d65e9 3454 if (error == -EAGAIN || error == -EDEADLK)
e7fd4179
DT		 3455 error = 0;
3456 out:
85e86edf 3457 dlm_unlock_recovery(ls);
e7fd4179
DT		 3458 dlm_put_lockspace(ls);
3459 return error;
3460}
3461
3462int dlm_unlock(dlm_lockspace_t *lockspace,
3463 uint32_t lkid,
3464 uint32_t flags,
3465 struct dlm_lksb *lksb,
3466 void *astarg)
3467{
3468 struct dlm_ls *ls;
3469 struct dlm_lkb *lkb;
3470 struct dlm_args args;
3471 int error;
3472
3473 ls = dlm_find_lockspace_local(lockspace);
3474 if (!ls)
3475 return -EINVAL;
3476
85e86edf 3477 dlm_lock_recovery(ls);
e7fd4179
DT		 3478
3479 error = find_lkb(ls, lkid, &lkb);
3480 if (error)
3481 goto out;
3482
3483 error = set_unlock_args(flags, astarg, &args);
3484 if (error)
3485 goto out_put;
3486
3487 if (flags & DLM_LKF_CANCEL)
3488 error = cancel_lock(ls, lkb, &args);
3489 else
3490 error = unlock_lock(ls, lkb, &args);
3491
3492 if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL)
3493 error = 0;
ef0c2bb0
DT		 3494 if (error == -EBUSY && (flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)))
3495 error = 0;
e7fd4179 3496 out_put:
b3f58d8f 3497 dlm_put_lkb(lkb);
e7fd4179 3498 out:
85e86edf 3499 dlm_unlock_recovery(ls);
e7fd4179
DT		 3500 dlm_put_lockspace(ls);
3501 return error;
3502}
3503
3504/*
3505 * send/receive routines for remote operations and replies
3506 *
3507 * send_args
3508 * send_common
3509 * send_request receive_request
3510 * send_convert receive_convert
3511 * send_unlock receive_unlock
3512 * send_cancel receive_cancel
3513 * send_grant receive_grant
3514 * send_bast receive_bast
3515 * send_lookup receive_lookup
3516 * send_remove receive_remove
3517 *
3518 * send_common_reply
3519 * receive_request_reply send_request_reply
3520 * receive_convert_reply send_convert_reply
3521 * receive_unlock_reply send_unlock_reply
3522 * receive_cancel_reply send_cancel_reply
3523 * receive_lookup_reply send_lookup_reply
3524 */
3525
7e4dac33
DT		 3526static int _create_message(struct dlm_ls *ls, int mb_len,
3527 int to_nodeid, int mstype,
3528 struct dlm_message **ms_ret,
3529 struct dlm_mhandle **mh_ret)
e7fd4179
DT		 3530{
3531 struct dlm_message *ms;
3532 struct dlm_mhandle *mh;
3533 char *mb;
e7fd4179
DT		 3534
3535 /* get_buffer gives us a message handle (mh) that we need to
3536 pass into lowcomms_commit and a message buffer (mb) that we
3537 write our data into */
3538
573c24c4 3539 mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_NOFS, &mb);
e7fd4179
DT		 3540 if (!mh)
3541 return -ENOBUFS;
3542
3543 memset(mb, 0, mb_len);
3544
3545 ms = (struct dlm_message *) mb;
3546
3547 ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
7e4dac33 3548 ms->m_header.h_lockspace = ls->ls_global_id;
e7fd4179
DT		 3549 ms->m_header.h_nodeid = dlm_our_nodeid();
3550 ms->m_header.h_length = mb_len;
3551 ms->m_header.h_cmd = DLM_MSG;
3552
3553 ms->m_type = mstype;
3554
3555 *mh_ret = mh;
3556 *ms_ret = ms;
3557 return 0;
3558}
3559
7e4dac33
DT		 3560static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb,
3561 int to_nodeid, int mstype,
3562 struct dlm_message **ms_ret,
3563 struct dlm_mhandle **mh_ret)
3564{
3565 int mb_len = sizeof(struct dlm_message);
3566
3567 switch (mstype) {
3568 case DLM_MSG_REQUEST:
3569 case DLM_MSG_LOOKUP:
3570 case DLM_MSG_REMOVE:
3571 mb_len += r->res_length;
3572 break;
3573 case DLM_MSG_CONVERT:
3574 case DLM_MSG_UNLOCK:
3575 case DLM_MSG_REQUEST_REPLY:
3576 case DLM_MSG_CONVERT_REPLY:
3577 case DLM_MSG_GRANT:
3578 if (lkb && lkb->lkb_lvbptr)
3579 mb_len += r->res_ls->ls_lvblen;
3580 break;
3581 }
3582
3583 return _create_message(r->res_ls, mb_len, to_nodeid, mstype,
3584 ms_ret, mh_ret);
3585}
3586
e7fd4179
DT		 3587/* further lowcomms enhancements or alternate implementations may make
3588 the return value from this function useful at some point */
3589
3590static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms)
3591{
3592 dlm_message_out(ms);
3593 dlm_lowcomms_commit_buffer(mh);
3594 return 0;
3595}
3596
3597static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
3598 struct dlm_message *ms)
3599{
3600 ms->m_nodeid = lkb->lkb_nodeid;
3601 ms->m_pid = lkb->lkb_ownpid;
3602 ms->m_lkid = lkb->lkb_id;
3603 ms->m_remid = lkb->lkb_remid;
3604 ms->m_exflags = lkb->lkb_exflags;
3605 ms->m_sbflags = lkb->lkb_sbflags;
3606 ms->m_flags = lkb->lkb_flags;
3607 ms->m_lvbseq = lkb->lkb_lvbseq;
3608 ms->m_status = lkb->lkb_status;
3609 ms->m_grmode = lkb->lkb_grmode;
3610 ms->m_rqmode = lkb->lkb_rqmode;
3611 ms->m_hash = r->res_hash;
3612
3613 /* m_result and m_bastmode are set from function args,
3614 not from lkb fields */
3615
e5dae548 3616 if (lkb->lkb_bastfn)
8304d6f2 3617 ms->m_asts |= DLM_CB_BAST;
e5dae548 3618 if (lkb->lkb_astfn)
8304d6f2 3619 ms->m_asts |= DLM_CB_CAST;
e7fd4179 3620
da49f36f
DT		 3621 /* compare with switch in create_message; send_remove() doesn't
3622 use send_args() */
e7fd4179 3623
da49f36f
DT		 3624 switch (ms->m_type) {
3625 case DLM_MSG_REQUEST:
3626 case DLM_MSG_LOOKUP:
3627 memcpy(ms->m_extra, r->res_name, r->res_length);
3628 break;
3629 case DLM_MSG_CONVERT:
3630 case DLM_MSG_UNLOCK:
3631 case DLM_MSG_REQUEST_REPLY:
3632 case DLM_MSG_CONVERT_REPLY:
3633 case DLM_MSG_GRANT:
3634 if (!lkb->lkb_lvbptr)
3635 break;
e7fd4179 3636 memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
da49f36f
DT		 3637 break;
3638 }
e7fd4179
DT		 3639}
3640
3641static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype)
3642{
3643 struct dlm_message *ms;
3644 struct dlm_mhandle *mh;
3645 int to_nodeid, error;
3646
c6ff669b
DT		 3647 to_nodeid = r->res_nodeid;
3648
3649 error = add_to_waiters(lkb, mstype, to_nodeid);
ef0c2bb0
DT		 3650 if (error)
3651 return error;
e7fd4179 3652
e7fd4179
DT		 3653 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3654 if (error)
3655 goto fail;
3656
3657 send_args(r, lkb, ms);
3658
3659 error = send_message(mh, ms);
3660 if (error)
3661 goto fail;
3662 return 0;
3663
3664 fail:
ef0c2bb0 3665 remove_from_waiters(lkb, msg_reply_type(mstype));
e7fd4179
DT		 3666 return error;
3667}
3668
3669static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
3670{
3671 return send_common(r, lkb, DLM_MSG_REQUEST);
3672}
3673
3674static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
3675{
3676 int error;
3677
3678 error = send_common(r, lkb, DLM_MSG_CONVERT);
3679
3680 /* down conversions go without a reply from the master */
3681 if (!error && down_conversion(lkb)) {
ef0c2bb0 3682 remove_from_waiters(lkb, DLM_MSG_CONVERT_REPLY);
2a7ce0ed 3683 r->res_ls->ls_stub_ms.m_flags = DLM_IFL_STUB_MS;
ef0c2bb0 3684 r->res_ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
e7fd4179
DT		 3685 r->res_ls->ls_stub_ms.m_result = 0;
3686 __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms);
3687 }
3688
3689 return error;
3690}
3691
3692/* FIXME: if this lkb is the only lock we hold on the rsb, then set
3693 MASTER_UNCERTAIN to force the next request on the rsb to confirm
3694 that the master is still correct. */
3695
3696static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
3697{
3698 return send_common(r, lkb, DLM_MSG_UNLOCK);
3699}
3700
3701static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb)
3702{
3703 return send_common(r, lkb, DLM_MSG_CANCEL);
3704}
3705
3706static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb)
3707{
3708 struct dlm_message *ms;
3709 struct dlm_mhandle *mh;
3710 int to_nodeid, error;
3711
3712 to_nodeid = lkb->lkb_nodeid;
3713
3714 error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh);
3715 if (error)
3716 goto out;
3717
3718 send_args(r, lkb, ms);
3719
3720 ms->m_result = 0;
3721
3722 error = send_message(mh, ms);
3723 out:
3724 return error;
3725}
3726
3727static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode)
3728{
3729 struct dlm_message *ms;
3730 struct dlm_mhandle *mh;
3731 int to_nodeid, error;
3732
3733 to_nodeid = lkb->lkb_nodeid;
3734
3735 error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh);
3736 if (error)
3737 goto out;
3738
3739 send_args(r, lkb, ms);
3740
3741 ms->m_bastmode = mode;
3742
3743 error = send_message(mh, ms);
3744 out:
3745 return error;
3746}
3747
3748static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb)
3749{
3750 struct dlm_message *ms;
3751 struct dlm_mhandle *mh;
3752 int to_nodeid, error;
3753
c6ff669b
DT		 3754 to_nodeid = dlm_dir_nodeid(r);
3755
3756 error = add_to_waiters(lkb, DLM_MSG_LOOKUP, to_nodeid);
ef0c2bb0
DT		 3757 if (error)
3758 return error;
e7fd4179 3759
e7fd4179
DT		 3760 error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh);
3761 if (error)
3762 goto fail;
3763
3764 send_args(r, lkb, ms);
3765
3766 error = send_message(mh, ms);
3767 if (error)
3768 goto fail;
3769 return 0;
3770
3771 fail:
ef0c2bb0 3772 remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
e7fd4179
DT		 3773 return error;
3774}
3775
3776static int send_remove(struct dlm_rsb *r)
3777{
3778 struct dlm_message *ms;
3779 struct dlm_mhandle *mh;
3780 int to_nodeid, error;
3781
3782 to_nodeid = dlm_dir_nodeid(r);
3783
3784 error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh);
3785 if (error)
3786 goto out;
3787
3788 memcpy(ms->m_extra, r->res_name, r->res_length);
3789 ms->m_hash = r->res_hash;
3790
3791 error = send_message(mh, ms);
3792 out:
3793 return error;
3794}
3795
3796static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
3797 int mstype, int rv)
3798{
3799 struct dlm_message *ms;
3800 struct dlm_mhandle *mh;
3801 int to_nodeid, error;
3802
3803 to_nodeid = lkb->lkb_nodeid;
3804
3805 error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh);
3806 if (error)
3807 goto out;
3808
3809 send_args(r, lkb, ms);
3810
3811 ms->m_result = rv;
3812
3813 error = send_message(mh, ms);
3814 out:
3815 return error;
3816}
3817
3818static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3819{
3820 return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv);
3821}
3822
3823static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3824{
3825 return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv);
3826}
3827
3828static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3829{
3830 return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv);
3831}
3832
3833static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
3834{
3835 return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv);
3836}
3837
3838static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in,
3839 int ret_nodeid, int rv)
3840{
3841 struct dlm_rsb *r = &ls->ls_stub_rsb;
3842 struct dlm_message *ms;
3843 struct dlm_mhandle *mh;
3844 int error, nodeid = ms_in->m_header.h_nodeid;
3845
3846 error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh);
3847 if (error)
3848 goto out;
3849
3850 ms->m_lkid = ms_in->m_lkid;
3851 ms->m_result = rv;
3852 ms->m_nodeid = ret_nodeid;
3853
3854 error = send_message(mh, ms);
3855 out:
3856 return error;
3857}
3858
3859/* which args we save from a received message depends heavily on the type
3860 of message, unlike the send side where we can safely send everything about
3861 the lkb for any type of message */
3862
3863static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms)
3864{
3865 lkb->lkb_exflags = ms->m_exflags;
6f90a8b1 3866 lkb->lkb_sbflags = ms->m_sbflags;
e7fd4179
DT		 3867 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3868 (ms->m_flags & 0x0000FFFF);
3869}
3870
3871static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
3872{
2a7ce0ed
DT		 3873 if (ms->m_flags == DLM_IFL_STUB_MS)
3874 return;
3875
e7fd4179
DT		 3876 lkb->lkb_sbflags = ms->m_sbflags;
3877 lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) |
3878 (ms->m_flags & 0x0000FFFF);
3879}
3880
3881static int receive_extralen(struct dlm_message *ms)
3882{
3883 return (ms->m_header.h_length - sizeof(struct dlm_message));
3884}
3885
e7fd4179
DT		 3886static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb,
3887 struct dlm_message *ms)
3888{
3889 int len;
3890
3891 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3892 if (!lkb->lkb_lvbptr)
52bda2b5 3893 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 3894 if (!lkb->lkb_lvbptr)
3895 return -ENOMEM;
3896 len = receive_extralen(ms);
cfa805f6
BVA		 3897 if (len > ls->ls_lvblen)
3898 len = ls->ls_lvblen;
e7fd4179
DT		 3899 memcpy(lkb->lkb_lvbptr, ms->m_extra, len);
3900 }
3901 return 0;
3902}
3903
e5dae548
DT		 3904static void fake_bastfn(void *astparam, int mode)
3905{
3906 log_print("fake_bastfn should not be called");
3907}
3908
3909static void fake_astfn(void *astparam)
3910{
3911 log_print("fake_astfn should not be called");
3912}
3913
e7fd4179
DT		 3914static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3915 struct dlm_message *ms)
3916{
3917 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3918 lkb->lkb_ownpid = ms->m_pid;
3919 lkb->lkb_remid = ms->m_lkid;
3920 lkb->lkb_grmode = DLM_LOCK_IV;
3921 lkb->lkb_rqmode = ms->m_rqmode;
e5dae548 3922
8304d6f2
DT		 3923 lkb->lkb_bastfn = (ms->m_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
3924 lkb->lkb_astfn = (ms->m_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
e7fd4179 3925
8d07fd50
DT		 3926 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
3927 /* lkb was just created so there won't be an lvb yet */
52bda2b5 3928 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
8d07fd50
DT		 3929 if (!lkb->lkb_lvbptr)
3930 return -ENOMEM;
3931 }
e7fd4179
DT		 3932
3933 return 0;
3934}
3935
3936static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3937 struct dlm_message *ms)
3938{
e7fd4179
DT		 3939 if (lkb->lkb_status != DLM_LKSTS_GRANTED)
3940 return -EBUSY;
3941
e7fd4179
DT		 3942 if (receive_lvb(ls, lkb, ms))
3943 return -ENOMEM;
3944
3945 lkb->lkb_rqmode = ms->m_rqmode;
3946 lkb->lkb_lvbseq = ms->m_lvbseq;
3947
3948 return 0;
3949}
3950
3951static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
3952 struct dlm_message *ms)
3953{
e7fd4179
DT		 3954 if (receive_lvb(ls, lkb, ms))
3955 return -ENOMEM;
3956 return 0;
3957}
3958
3959/* We fill in the stub-lkb fields with the info that send_xxxx_reply()
3960 uses to send a reply and that the remote end uses to process the reply. */
3961
3962static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms)
3963{
3964 struct dlm_lkb *lkb = &ls->ls_stub_lkb;
3965 lkb->lkb_nodeid = ms->m_header.h_nodeid;
3966 lkb->lkb_remid = ms->m_lkid;
3967}
3968
c54e04b0
DT		 3969/* This is called after the rsb is locked so that we can safely inspect
3970 fields in the lkb. */
3971
3972static int validate_message(struct dlm_lkb *lkb, struct dlm_message *ms)
3973{
3974 int from = ms->m_header.h_nodeid;
3975 int error = 0;
3976
3977 switch (ms->m_type) {
3978 case DLM_MSG_CONVERT:
3979 case DLM_MSG_UNLOCK:
3980 case DLM_MSG_CANCEL:
3981 if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
3982 error = -EINVAL;
3983 break;
3984
3985 case DLM_MSG_CONVERT_REPLY:
3986 case DLM_MSG_UNLOCK_REPLY:
3987 case DLM_MSG_CANCEL_REPLY:
3988 case DLM_MSG_GRANT:
3989 case DLM_MSG_BAST:
3990 if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
3991 error = -EINVAL;
3992 break;
3993
3994 case DLM_MSG_REQUEST_REPLY:
3995 if (!is_process_copy(lkb))
3996 error = -EINVAL;
3997 else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
3998 error = -EINVAL;
3999 break;
4000
4001 default:
4002 error = -EINVAL;
4003 }
4004
4005 if (error)
4006 log_error(lkb->lkb_resource->res_ls,
4007 "ignore invalid message %d from %d %x %x %x %d",
4008 ms->m_type, from, lkb->lkb_id, lkb->lkb_remid,
4009 lkb->lkb_flags, lkb->lkb_nodeid);
4010 return error;
4011}
4012
96006ea6
DT		 4013static void send_repeat_remove(struct dlm_ls *ls, char *ms_name, int len)
4014{
4015 char name[DLM_RESNAME_MAXLEN + 1];
4016 struct dlm_message *ms;
4017 struct dlm_mhandle *mh;
4018 struct dlm_rsb *r;
4019 uint32_t hash, b;
4020 int rv, dir_nodeid;
4021
4022 memset(name, 0, sizeof(name));
4023 memcpy(name, ms_name, len);
4024
4025 hash = jhash(name, len, 0);
4026 b = hash & (ls->ls_rsbtbl_size - 1);
4027
4028 dir_nodeid = dlm_hash2nodeid(ls, hash);
4029
4030 log_error(ls, "send_repeat_remove dir %d %s", dir_nodeid, name);
4031
4032 spin_lock(&ls->ls_rsbtbl[b].lock);
4033 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4034 if (!rv) {
4035 spin_unlock(&ls->ls_rsbtbl[b].lock);
4036 log_error(ls, "repeat_remove on keep %s", name);
4037 return;
4038 }
4039
4040 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4041 if (!rv) {
4042 spin_unlock(&ls->ls_rsbtbl[b].lock);
4043 log_error(ls, "repeat_remove on toss %s", name);
4044 return;
4045 }
4046
4047 /* use ls->remove_name2 to avoid conflict with shrink? */
4048
4049 spin_lock(&ls->ls_remove_spin);
4050 ls->ls_remove_len = len;
4051 memcpy(ls->ls_remove_name, name, DLM_RESNAME_MAXLEN);
4052 spin_unlock(&ls->ls_remove_spin);
4053 spin_unlock(&ls->ls_rsbtbl[b].lock);
4054
4055 rv = _create_message(ls, sizeof(struct dlm_message) + len,
4056 dir_nodeid, DLM_MSG_REMOVE, &ms, &mh);
4057 if (rv)
4058 return;
4059
4060 memcpy(ms->m_extra, name, len);
4061 ms->m_hash = hash;
4062
4063 send_message(mh, ms);
4064
4065 spin_lock(&ls->ls_remove_spin);
4066 ls->ls_remove_len = 0;
4067 memset(ls->ls_remove_name, 0, DLM_RESNAME_MAXLEN);
4068 spin_unlock(&ls->ls_remove_spin);
4069}
4070
6d40c4a7 4071static int receive_request(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4072{
4073 struct dlm_lkb *lkb;
4074 struct dlm_rsb *r;
c04fecb4 4075 int from_nodeid;
96006ea6 4076 int error, namelen = 0;
e7fd4179 4077
c04fecb4
DT		 4078 from_nodeid = ms->m_header.h_nodeid;
4079
e7fd4179
DT		 4080 error = create_lkb(ls, &lkb);
4081 if (error)
4082 goto fail;
4083
4084 receive_flags(lkb, ms);
4085 lkb->lkb_flags |= DLM_IFL_MSTCPY;
4086 error = receive_request_args(ls, lkb, ms);
4087 if (error) {
b3f58d8f 4088 __put_lkb(ls, lkb);
e7fd4179
DT		 4089 goto fail;
4090 }
4091
c04fecb4
DT		 4092 /* The dir node is the authority on whether we are the master
4093 for this rsb or not, so if the master sends us a request, we should
4094 recreate the rsb if we've destroyed it. This race happens when we
4095 send a remove message to the dir node at the same time that the dir
4096 node sends us a request for the rsb. */
4097
e7fd4179
DT		 4098 namelen = receive_extralen(ms);
4099
c04fecb4
DT		 4100 error = find_rsb(ls, ms->m_extra, namelen, from_nodeid,
4101 R_RECEIVE_REQUEST, &r);
e7fd4179 4102 if (error) {
b3f58d8f 4103 __put_lkb(ls, lkb);
e7fd4179
DT		 4104 goto fail;
4105 }
4106
4107 lock_rsb(r);
4108
c04fecb4
DT		 4109 if (r->res_master_nodeid != dlm_our_nodeid()) {
4110 error = validate_master_nodeid(ls, r, from_nodeid);
4111 if (error) {
4112 unlock_rsb(r);
4113 put_rsb(r);
4114 __put_lkb(ls, lkb);
4115 goto fail;
4116 }
4117 }
4118
e7fd4179
DT		 4119 attach_lkb(r, lkb);
4120 error = do_request(r, lkb);
4121 send_request_reply(r, lkb, error);
cf6620ac 4122 do_request_effects(r, lkb, error);
e7fd4179
DT		 4123
4124 unlock_rsb(r);
4125 put_rsb(r);
4126
4127 if (error == -EINPROGRESS)
4128 error = 0;
4129 if (error)
b3f58d8f 4130 dlm_put_lkb(lkb);
6d40c4a7 4131 return 0;
e7fd4179
DT		 4132
4133 fail:
c04fecb4
DT		 4134 /* TODO: instead of returning ENOTBLK, add the lkb to res_lookup
4135 and do this receive_request again from process_lookup_list once
4136 we get the lookup reply. This would avoid a many repeated
4137 ENOTBLK request failures when the lookup reply designating us
4138 as master is delayed. */
4139
4140 /* We could repeatedly return -EBADR here if our send_remove() is
4141 delayed in being sent/arriving/being processed on the dir node.
4142 Another node would repeatedly lookup up the master, and the dir
4143 node would continue returning our nodeid until our send_remove
96006ea6
DT		 4144 took effect.
4145
4146 We send another remove message in case our previous send_remove
4147 was lost/ignored/missed somehow. */
c04fecb4
DT		 4148
4149 if (error != -ENOTBLK) {
4150 log_limit(ls, "receive_request %x from %d %d",
4151 ms->m_lkid, from_nodeid, error);
4152 }
4153
96006ea6
DT		 4154 if (namelen && error == -EBADR) {
4155 send_repeat_remove(ls, ms->m_extra, namelen);
4156 msleep(1000);
4157 }
4158
e7fd4179
DT		 4159 setup_stub_lkb(ls, ms);
4160 send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4161 return error;
e7fd4179
DT		 4162}
4163
6d40c4a7 4164static int receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4165{
4166 struct dlm_lkb *lkb;
4167 struct dlm_rsb *r;
90135925 4168 int error, reply = 1;
e7fd4179
DT		 4169
4170 error = find_lkb(ls, ms->m_remid, &lkb);
4171 if (error)
4172 goto fail;
4173
6d40c4a7 4174 if (lkb->lkb_remid != ms->m_lkid) {
4875647a
DT		 4175 log_error(ls, "receive_convert %x remid %x recover_seq %llu "
4176 "remote %d %x", lkb->lkb_id, lkb->lkb_remid,
4177 (unsigned long long)lkb->lkb_recover_seq,
6d40c4a7
DT		 4178 ms->m_header.h_nodeid, ms->m_lkid);
4179 error = -ENOENT;
4180 goto fail;
4181 }
4182
e7fd4179
DT		 4183 r = lkb->lkb_resource;
4184
4185 hold_rsb(r);
4186 lock_rsb(r);
4187
c54e04b0
DT		 4188 error = validate_message(lkb, ms);
4189 if (error)
4190 goto out;
4191
e7fd4179 4192 receive_flags(lkb, ms);
cf6620ac 4193
e7fd4179 4194 error = receive_convert_args(ls, lkb, ms);
cf6620ac
DT		 4195 if (error) {
4196 send_convert_reply(r, lkb, error);
4197 goto out;
4198 }
4199
e7fd4179
DT		 4200 reply = !down_conversion(lkb);
4201
4202 error = do_convert(r, lkb);
e7fd4179
DT		 4203 if (reply)
4204 send_convert_reply(r, lkb, error);
cf6620ac 4205 do_convert_effects(r, lkb, error);
c54e04b0 4206 out:
e7fd4179
DT		 4207 unlock_rsb(r);
4208 put_rsb(r);
b3f58d8f 4209 dlm_put_lkb(lkb);
6d40c4a7 4210 return 0;
e7fd4179
DT		 4211
4212 fail:
4213 setup_stub_lkb(ls, ms);
4214 send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4215 return error;
e7fd4179
DT		 4216}
4217
6d40c4a7 4218static int receive_unlock(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4219{
4220 struct dlm_lkb *lkb;
4221 struct dlm_rsb *r;
4222 int error;
4223
4224 error = find_lkb(ls, ms->m_remid, &lkb);
4225 if (error)
4226 goto fail;
4227
6d40c4a7
DT		 4228 if (lkb->lkb_remid != ms->m_lkid) {
4229 log_error(ls, "receive_unlock %x remid %x remote %d %x",
4230 lkb->lkb_id, lkb->lkb_remid,
4231 ms->m_header.h_nodeid, ms->m_lkid);
4232 error = -ENOENT;
4233 goto fail;
4234 }
4235
e7fd4179
DT		 4236 r = lkb->lkb_resource;
4237
4238 hold_rsb(r);
4239 lock_rsb(r);
4240
c54e04b0
DT		 4241 error = validate_message(lkb, ms);
4242 if (error)
4243 goto out;
4244
e7fd4179 4245 receive_flags(lkb, ms);
cf6620ac 4246
e7fd4179 4247 error = receive_unlock_args(ls, lkb, ms);
cf6620ac
DT		 4248 if (error) {
4249 send_unlock_reply(r, lkb, error);
4250 goto out;
4251 }
e7fd4179
DT		 4252
4253 error = do_unlock(r, lkb);
e7fd4179 4254 send_unlock_reply(r, lkb, error);
cf6620ac 4255 do_unlock_effects(r, lkb, error);
c54e04b0 4256 out:
e7fd4179
DT		 4257 unlock_rsb(r);
4258 put_rsb(r);
b3f58d8f 4259 dlm_put_lkb(lkb);
6d40c4a7 4260 return 0;
e7fd4179
DT		 4261
4262 fail:
4263 setup_stub_lkb(ls, ms);
4264 send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4265 return error;
e7fd4179
DT		 4266}
4267
6d40c4a7 4268static int receive_cancel(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4269{
4270 struct dlm_lkb *lkb;
4271 struct dlm_rsb *r;
4272 int error;
4273
4274 error = find_lkb(ls, ms->m_remid, &lkb);
4275 if (error)
4276 goto fail;
4277
4278 receive_flags(lkb, ms);
4279
4280 r = lkb->lkb_resource;
4281
4282 hold_rsb(r);
4283 lock_rsb(r);
4284
c54e04b0
DT		 4285 error = validate_message(lkb, ms);
4286 if (error)
4287 goto out;
4288
e7fd4179
DT		 4289 error = do_cancel(r, lkb);
4290 send_cancel_reply(r, lkb, error);
cf6620ac 4291 do_cancel_effects(r, lkb, error);
c54e04b0 4292 out:
e7fd4179
DT		 4293 unlock_rsb(r);
4294 put_rsb(r);
b3f58d8f 4295 dlm_put_lkb(lkb);
6d40c4a7 4296 return 0;
e7fd4179
DT		 4297
4298 fail:
4299 setup_stub_lkb(ls, ms);
4300 send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error);
6d40c4a7 4301 return error;
e7fd4179
DT		 4302}
4303
6d40c4a7 4304static int receive_grant(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4305{
4306 struct dlm_lkb *lkb;
4307 struct dlm_rsb *r;
4308 int error;
4309
4310 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4311 if (error)
4312 return error;
e7fd4179
DT		 4313
4314 r = lkb->lkb_resource;
4315
4316 hold_rsb(r);
4317 lock_rsb(r);
4318
c54e04b0
DT		 4319 error = validate_message(lkb, ms);
4320 if (error)
4321 goto out;
4322
e7fd4179 4323 receive_flags_reply(lkb, ms);
7d3c1feb
DT		 4324 if (is_altmode(lkb))
4325 munge_altmode(lkb, ms);
e7fd4179
DT		 4326 grant_lock_pc(r, lkb, ms);
4327 queue_cast(r, lkb, 0);
c54e04b0 4328 out:
e7fd4179
DT		 4329 unlock_rsb(r);
4330 put_rsb(r);
b3f58d8f 4331 dlm_put_lkb(lkb);
6d40c4a7 4332 return 0;
e7fd4179
DT		 4333}
4334
6d40c4a7 4335static int receive_bast(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4336{
4337 struct dlm_lkb *lkb;
4338 struct dlm_rsb *r;
4339 int error;
4340
4341 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4342 if (error)
4343 return error;
e7fd4179
DT		 4344
4345 r = lkb->lkb_resource;
4346
4347 hold_rsb(r);
4348 lock_rsb(r);
4349
c54e04b0
DT		 4350 error = validate_message(lkb, ms);
4351 if (error)
4352 goto out;
e7fd4179 4353
c54e04b0 4354 queue_bast(r, lkb, ms->m_bastmode);
4875647a 4355 lkb->lkb_highbast = ms->m_bastmode;
c54e04b0 4356 out:
e7fd4179
DT		 4357 unlock_rsb(r);
4358 put_rsb(r);
b3f58d8f 4359 dlm_put_lkb(lkb);
6d40c4a7 4360 return 0;
e7fd4179
DT		 4361}
4362
4363static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms)
4364{
c04fecb4 4365 int len, error, ret_nodeid, from_nodeid, our_nodeid;
e7fd4179
DT		 4366
4367 from_nodeid = ms->m_header.h_nodeid;
4368 our_nodeid = dlm_our_nodeid();
4369
4370 len = receive_extralen(ms);
4371
c04fecb4
DT		 4372 error = dlm_master_lookup(ls, from_nodeid, ms->m_extra, len, 0,
4373 &ret_nodeid, NULL);
e7fd4179
DT		 4374
4375 /* Optimization: we're master so treat lookup as a request */
4376 if (!error && ret_nodeid == our_nodeid) {
4377 receive_request(ls, ms);
4378 return;
4379 }
e7fd4179
DT		 4380 send_lookup_reply(ls, ms, ret_nodeid, error);
4381}
4382
4383static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms)
4384{
c04fecb4
DT		 4385 char name[DLM_RESNAME_MAXLEN+1];
4386 struct dlm_rsb *r;
4387 uint32_t hash, b;
4388 int rv, len, dir_nodeid, from_nodeid;
e7fd4179
DT		 4389
4390 from_nodeid = ms->m_header.h_nodeid;
4391
4392 len = receive_extralen(ms);
4393
c04fecb4
DT		 4394 if (len > DLM_RESNAME_MAXLEN) {
4395 log_error(ls, "receive_remove from %d bad len %d",
4396 from_nodeid, len);
4397 return;
4398 }
4399
e7fd4179
DT		 4400 dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash);
4401 if (dir_nodeid != dlm_our_nodeid()) {
c04fecb4
DT		 4402 log_error(ls, "receive_remove from %d bad nodeid %d",
4403 from_nodeid, dir_nodeid);
e7fd4179
DT		 4404 return;
4405 }
4406
c04fecb4
DT		 4407 /* Look for name on rsbtbl.toss, if it's there, kill it.
4408 If it's on rsbtbl.keep, it's being used, and we should ignore this
4409 message. This is an expected race between the dir node sending a
4410 request to the master node at the same time as the master node sends
4411 a remove to the dir node. The resolution to that race is for the
4412 dir node to ignore the remove message, and the master node to
4413 recreate the master rsb when it gets a request from the dir node for
4414 an rsb it doesn't have. */
4415
4416 memset(name, 0, sizeof(name));
4417 memcpy(name, ms->m_extra, len);
4418
4419 hash = jhash(name, len, 0);
4420 b = hash & (ls->ls_rsbtbl_size - 1);
4421
4422 spin_lock(&ls->ls_rsbtbl[b].lock);
4423
4424 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, &r);
4425 if (rv) {
4426 /* verify the rsb is on keep list per comment above */
4427 rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, &r);
4428 if (rv) {
4429 /* should not happen */
4430 log_error(ls, "receive_remove from %d not found %s",
4431 from_nodeid, name);
4432 spin_unlock(&ls->ls_rsbtbl[b].lock);
4433 return;
4434 }
4435 if (r->res_master_nodeid != from_nodeid) {
4436 /* should not happen */
4437 log_error(ls, "receive_remove keep from %d master %d",
4438 from_nodeid, r->res_master_nodeid);
4439 dlm_print_rsb(r);
4440 spin_unlock(&ls->ls_rsbtbl[b].lock);
4441 return;
4442 }
4443
4444 log_debug(ls, "receive_remove from %d master %d first %x %s",
4445 from_nodeid, r->res_master_nodeid, r->res_first_lkid,
4446 name);
4447 spin_unlock(&ls->ls_rsbtbl[b].lock);
4448 return;
4449 }
4450
4451 if (r->res_master_nodeid != from_nodeid) {
4452 log_error(ls, "receive_remove toss from %d master %d",
4453 from_nodeid, r->res_master_nodeid);
4454 dlm_print_rsb(r);
4455 spin_unlock(&ls->ls_rsbtbl[b].lock);
4456 return;
4457 }
4458
4459 if (kref_put(&r->res_ref, kill_rsb)) {
4460 rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss);
4461 spin_unlock(&ls->ls_rsbtbl[b].lock);
4462 dlm_free_rsb(r);
4463 } else {
4464 log_error(ls, "receive_remove from %d rsb ref error",
4465 from_nodeid);
4466 dlm_print_rsb(r);
4467 spin_unlock(&ls->ls_rsbtbl[b].lock);
4468 }
e7fd4179
DT		 4469}
4470
8499137d
DT		 4471static void receive_purge(struct dlm_ls *ls, struct dlm_message *ms)
4472{
4473 do_purge(ls, ms->m_nodeid, ms->m_pid);
4474}
4475
6d40c4a7 4476static int receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4477{
4478 struct dlm_lkb *lkb;
4479 struct dlm_rsb *r;
ef0c2bb0 4480 int error, mstype, result;
c04fecb4 4481 int from_nodeid = ms->m_header.h_nodeid;
e7fd4179
DT		 4482
4483 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4484 if (error)
4485 return error;
e7fd4179 4486
e7fd4179
DT		 4487 r = lkb->lkb_resource;
4488 hold_rsb(r);
4489 lock_rsb(r);
4490
c54e04b0
DT		 4491 error = validate_message(lkb, ms);
4492 if (error)
4493 goto out;
4494
ef0c2bb0
DT		 4495 mstype = lkb->lkb_wait_type;
4496 error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
4875647a
DT		 4497 if (error) {
4498 log_error(ls, "receive_request_reply %x remote %d %x result %d",
c04fecb4 4499 lkb->lkb_id, from_nodeid, ms->m_lkid, ms->m_result);
4875647a 4500 dlm_dump_rsb(r);
ef0c2bb0 4501 goto out;
4875647a 4502 }
ef0c2bb0 4503
e7fd4179
DT		 4504 /* Optimization: the dir node was also the master, so it took our
4505 lookup as a request and sent request reply instead of lookup reply */
4506 if (mstype == DLM_MSG_LOOKUP) {
c04fecb4
DT		 4507 r->res_master_nodeid = from_nodeid;
4508 r->res_nodeid = from_nodeid;
4509 lkb->lkb_nodeid = from_nodeid;
e7fd4179
DT		 4510 }
4511
ef0c2bb0
DT		 4512 /* this is the value returned from do_request() on the master */
4513 result = ms->m_result;
4514
4515 switch (result) {
e7fd4179 4516 case -EAGAIN:
ef0c2bb0 4517 /* request would block (be queued) on remote master */
e7fd4179
DT		 4518 queue_cast(r, lkb, -EAGAIN);
4519 confirm_master(r, -EAGAIN);
ef0c2bb0 4520 unhold_lkb(lkb); /* undoes create_lkb() */
e7fd4179
DT		 4521 break;
4522
4523 case -EINPROGRESS:
4524 case 0:
4525 /* request was queued or granted on remote master */
4526 receive_flags_reply(lkb, ms);
4527 lkb->lkb_remid = ms->m_lkid;
7d3c1feb
DT		 4528 if (is_altmode(lkb))
4529 munge_altmode(lkb, ms);
3ae1acf9 4530 if (result) {
e7fd4179 4531 add_lkb(r, lkb, DLM_LKSTS_WAITING);
3ae1acf9
DT		 4532 add_timeout(lkb);
4533 } else {
e7fd4179
DT		 4534 grant_lock_pc(r, lkb, ms);
4535 queue_cast(r, lkb, 0);
4536 }
ef0c2bb0 4537 confirm_master(r, result);
e7fd4179
DT		 4538 break;
4539
597d0cae 4540 case -EBADR:
e7fd4179
DT		 4541 case -ENOTBLK:
4542 /* find_rsb failed to find rsb or rsb wasn't master */
c04fecb4
DT		 4543 log_limit(ls, "receive_request_reply %x from %d %d "
4544 "master %d dir %d first %x %s", lkb->lkb_id,
4545 from_nodeid, result, r->res_master_nodeid,
4546 r->res_dir_nodeid, r->res_first_lkid, r->res_name);
4547
4548 if (r->res_dir_nodeid != dlm_our_nodeid() &&
4549 r->res_master_nodeid != dlm_our_nodeid()) {
4550 /* cause _request_lock->set_master->send_lookup */
4551 r->res_master_nodeid = 0;
4552 r->res_nodeid = -1;
4553 lkb->lkb_nodeid = -1;
4554 }
ef0c2bb0
DT		 4555
4556 if (is_overlap(lkb)) {
4557 /* we'll ignore error in cancel/unlock reply */
4558 queue_cast_overlap(r, lkb);
aec64e1b 4559 confirm_master(r, result);
ef0c2bb0 4560 unhold_lkb(lkb); /* undoes create_lkb() */
c04fecb4 4561 } else {
ef0c2bb0 4562 _request_lock(r, lkb);
c04fecb4
DT		 4563
4564 if (r->res_master_nodeid == dlm_our_nodeid())
4565 confirm_master(r, 0);
4566 }
e7fd4179
DT		 4567 break;
4568
4569 default:
ef0c2bb0
DT		 4570 log_error(ls, "receive_request_reply %x error %d",
4571 lkb->lkb_id, result);
e7fd4179
DT		 4572 }
4573
ef0c2bb0
DT		 4574 if (is_overlap_unlock(lkb) && (result == 0 || result == -EINPROGRESS)) {
4575 log_debug(ls, "receive_request_reply %x result %d unlock",
4576 lkb->lkb_id, result);
4577 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4578 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4579 send_unlock(r, lkb);
4580 } else if (is_overlap_cancel(lkb) && (result == -EINPROGRESS)) {
4581 log_debug(ls, "receive_request_reply %x cancel", lkb->lkb_id);
4582 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4583 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4584 send_cancel(r, lkb);
4585 } else {
4586 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
4587 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
4588 }
4589 out:
e7fd4179
DT		 4590 unlock_rsb(r);
4591 put_rsb(r);
b3f58d8f 4592 dlm_put_lkb(lkb);
6d40c4a7 4593 return 0;
e7fd4179
DT		 4594}
4595
4596static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb,
4597 struct dlm_message *ms)
4598{
e7fd4179 4599 /* this is the value returned from do_convert() on the master */
ef0c2bb0 4600 switch (ms->m_result) {
e7fd4179
DT		 4601 case -EAGAIN:
4602 /* convert would block (be queued) on remote master */
4603 queue_cast(r, lkb, -EAGAIN);
4604 break;
4605
c85d65e9
DT		 4606 case -EDEADLK:
4607 receive_flags_reply(lkb, ms);
4608 revert_lock_pc(r, lkb);
4609 queue_cast(r, lkb, -EDEADLK);
4610 break;
4611
e7fd4179
DT		 4612 case -EINPROGRESS:
4613 /* convert was queued on remote master */
7d3c1feb
DT		 4614 receive_flags_reply(lkb, ms);
4615 if (is_demoted(lkb))
2a7ce0ed 4616 munge_demoted(lkb);
e7fd4179
DT		 4617 del_lkb(r, lkb);
4618 add_lkb(r, lkb, DLM_LKSTS_CONVERT);
3ae1acf9 4619 add_timeout(lkb);
e7fd4179
DT		 4620 break;
4621
4622 case 0:
4623 /* convert was granted on remote master */
4624 receive_flags_reply(lkb, ms);
7d3c1feb 4625 if (is_demoted(lkb))
2a7ce0ed 4626 munge_demoted(lkb);
e7fd4179
DT		 4627 grant_lock_pc(r, lkb, ms);
4628 queue_cast(r, lkb, 0);
4629 break;
4630
4631 default:
6d40c4a7
DT		 4632 log_error(r->res_ls, "receive_convert_reply %x remote %d %x %d",
4633 lkb->lkb_id, ms->m_header.h_nodeid, ms->m_lkid,
4634 ms->m_result);
4635 dlm_print_rsb(r);
4636 dlm_print_lkb(lkb);
e7fd4179
DT		 4637 }
4638}
4639
4640static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4641{
4642 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 4643 int error;
e7fd4179
DT		 4644
4645 hold_rsb(r);
4646 lock_rsb(r);
4647
c54e04b0
DT		 4648 error = validate_message(lkb, ms);
4649 if (error)
4650 goto out;
4651
ef0c2bb0
DT		 4652 /* stub reply can happen with waiters_mutex held */
4653 error = remove_from_waiters_ms(lkb, ms);
4654 if (error)
4655 goto out;
e7fd4179 4656
ef0c2bb0
DT		 4657 __receive_convert_reply(r, lkb, ms);
4658 out:
e7fd4179
DT		 4659 unlock_rsb(r);
4660 put_rsb(r);
4661}
4662
6d40c4a7 4663static int receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4664{
4665 struct dlm_lkb *lkb;
4666 int error;
4667
4668 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4669 if (error)
4670 return error;
e7fd4179 4671
e7fd4179 4672 _receive_convert_reply(lkb, ms);
b3f58d8f 4673 dlm_put_lkb(lkb);
6d40c4a7 4674 return 0;
e7fd4179
DT		 4675}
4676
4677static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4678{
4679 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 4680 int error;
e7fd4179
DT		 4681
4682 hold_rsb(r);
4683 lock_rsb(r);
4684
c54e04b0
DT		 4685 error = validate_message(lkb, ms);
4686 if (error)
4687 goto out;
4688
ef0c2bb0
DT		 4689 /* stub reply can happen with waiters_mutex held */
4690 error = remove_from_waiters_ms(lkb, ms);
4691 if (error)
4692 goto out;
4693
e7fd4179
DT		 4694 /* this is the value returned from do_unlock() on the master */
4695
ef0c2bb0 4696 switch (ms->m_result) {
e7fd4179
DT		 4697 case -DLM_EUNLOCK:
4698 receive_flags_reply(lkb, ms);
4699 remove_lock_pc(r, lkb);
4700 queue_cast(r, lkb, -DLM_EUNLOCK);
4701 break;
ef0c2bb0
DT		 4702 case -ENOENT:
4703 break;
e7fd4179 4704 default:
ef0c2bb0
DT		 4705 log_error(r->res_ls, "receive_unlock_reply %x error %d",
4706 lkb->lkb_id, ms->m_result);
e7fd4179 4707 }
ef0c2bb0 4708 out:
e7fd4179
DT		 4709 unlock_rsb(r);
4710 put_rsb(r);
4711}
4712
6d40c4a7 4713static int receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4714{
4715 struct dlm_lkb *lkb;
4716 int error;
4717
4718 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4719 if (error)
4720 return error;
e7fd4179 4721
e7fd4179 4722 _receive_unlock_reply(lkb, ms);
b3f58d8f 4723 dlm_put_lkb(lkb);
6d40c4a7 4724 return 0;
e7fd4179
DT		 4725}
4726
4727static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
4728{
4729 struct dlm_rsb *r = lkb->lkb_resource;
ef0c2bb0 4730 int error;
e7fd4179
DT		 4731
4732 hold_rsb(r);
4733 lock_rsb(r);
4734
c54e04b0
DT		 4735 error = validate_message(lkb, ms);
4736 if (error)
4737 goto out;
4738
ef0c2bb0
DT		 4739 /* stub reply can happen with waiters_mutex held */
4740 error = remove_from_waiters_ms(lkb, ms);
4741 if (error)
4742 goto out;
4743
e7fd4179
DT		 4744 /* this is the value returned from do_cancel() on the master */
4745
ef0c2bb0 4746 switch (ms->m_result) {
e7fd4179
DT		 4747 case -DLM_ECANCEL:
4748 receive_flags_reply(lkb, ms);
4749 revert_lock_pc(r, lkb);
84d8cd69 4750 queue_cast(r, lkb, -DLM_ECANCEL);
ef0c2bb0
DT		 4751 break;
4752 case 0:
e7fd4179
DT		 4753 break;
4754 default:
ef0c2bb0
DT		 4755 log_error(r->res_ls, "receive_cancel_reply %x error %d",
4756 lkb->lkb_id, ms->m_result);
e7fd4179 4757 }
ef0c2bb0 4758 out:
e7fd4179
DT		 4759 unlock_rsb(r);
4760 put_rsb(r);
4761}
4762
6d40c4a7 4763static int receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms)
e7fd4179
DT		 4764{
4765 struct dlm_lkb *lkb;
4766 int error;
4767
4768 error = find_lkb(ls, ms->m_remid, &lkb);
6d40c4a7
DT		 4769 if (error)
4770 return error;
e7fd4179 4771
e7fd4179 4772 _receive_cancel_reply(lkb, ms);
b3f58d8f 4773 dlm_put_lkb(lkb);
6d40c4a7 4774 return 0;
e7fd4179
DT		 4775}
4776
4777static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
4778{
4779 struct dlm_lkb *lkb;
4780 struct dlm_rsb *r;
4781 int error, ret_nodeid;
c04fecb4 4782 int do_lookup_list = 0;
e7fd4179
DT		 4783
4784 error = find_lkb(ls, ms->m_lkid, &lkb);
4785 if (error) {
6d40c4a7 4786 log_error(ls, "receive_lookup_reply no lkid %x", ms->m_lkid);
e7fd4179
DT		 4787 return;
4788 }
4789
c04fecb4 4790 /* ms->m_result is the value returned by dlm_master_lookup on dir node
e7fd4179 4791 FIXME: will a non-zero error ever be returned? */
e7fd4179
DT		 4792
4793 r = lkb->lkb_resource;
4794 hold_rsb(r);
4795 lock_rsb(r);
4796
ef0c2bb0
DT		 4797 error = remove_from_waiters(lkb, DLM_MSG_LOOKUP_REPLY);
4798 if (error)
4799 goto out;
4800
e7fd4179 4801 ret_nodeid = ms->m_nodeid;
c04fecb4
DT		 4802
4803 /* We sometimes receive a request from the dir node for this
4804 rsb before we've received the dir node's loookup_reply for it.
4805 The request from the dir node implies we're the master, so we set
4806 ourself as master in receive_request_reply, and verify here that
4807 we are indeed the master. */
4808
4809 if (r->res_master_nodeid && (r->res_master_nodeid != ret_nodeid)) {
4810 /* This should never happen */
4811 log_error(ls, "receive_lookup_reply %x from %d ret %d "
4812 "master %d dir %d our %d first %x %s",
4813 lkb->lkb_id, ms->m_header.h_nodeid, ret_nodeid,
4814 r->res_master_nodeid, r->res_dir_nodeid,
4815 dlm_our_nodeid(), r->res_first_lkid, r->res_name);
4816 }
4817
e7fd4179 4818 if (ret_nodeid == dlm_our_nodeid()) {
c04fecb4 4819 r->res_master_nodeid = ret_nodeid;
e7fd4179 4820 r->res_nodeid = 0;
c04fecb4 4821 do_lookup_list = 1;
e7fd4179 4822 r->res_first_lkid = 0;
c04fecb4
DT		 4823 } else if (ret_nodeid == -1) {
4824 /* the remote node doesn't believe it's the dir node */
4825 log_error(ls, "receive_lookup_reply %x from %d bad ret_nodeid",
4826 lkb->lkb_id, ms->m_header.h_nodeid);
4827 r->res_master_nodeid = 0;
4828 r->res_nodeid = -1;
4829 lkb->lkb_nodeid = -1;
e7fd4179 4830 } else {
c04fecb4
DT		 4831 /* set_master() will set lkb_nodeid from r */
4832 r->res_master_nodeid = ret_nodeid;
e7fd4179
DT		 4833 r->res_nodeid = ret_nodeid;
4834 }
4835
ef0c2bb0
DT		 4836 if (is_overlap(lkb)) {
4837 log_debug(ls, "receive_lookup_reply %x unlock %x",
4838 lkb->lkb_id, lkb->lkb_flags);
4839 queue_cast_overlap(r, lkb);
4840 unhold_lkb(lkb); /* undoes create_lkb() */
4841 goto out_list;
4842 }
4843
e7fd4179
DT		 4844 _request_lock(r, lkb);
4845
ef0c2bb0 4846 out_list:
c04fecb4 4847 if (do_lookup_list)
e7fd4179 4848 process_lookup_list(r);
ef0c2bb0 4849 out:
e7fd4179
DT		 4850 unlock_rsb(r);
4851 put_rsb(r);
b3f58d8f 4852 dlm_put_lkb(lkb);
e7fd4179
DT		 4853}
4854
6d40c4a7
DT		 4855static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4856 uint32_t saved_seq)
e7fd4179 4857{
6d40c4a7
DT		 4858 int error = 0, noent = 0;
4859
46b43eed 4860 if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
c04fecb4 4861 log_limit(ls, "receive %d from non-member %d %x %x %d",
46b43eed
DT		 4862 ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
4863 ms->m_remid, ms->m_result);
4864 return;
4865 }
4866
e7fd4179
DT		 4867 switch (ms->m_type) {
4868
4869 /* messages sent to a master node */
4870
4871 case DLM_MSG_REQUEST:
6d40c4a7 4872 error = receive_request(ls, ms);
e7fd4179
DT		 4873 break;
4874
4875 case DLM_MSG_CONVERT:
6d40c4a7 4876 error = receive_convert(ls, ms);
e7fd4179
DT		 4877 break;
4878
4879 case DLM_MSG_UNLOCK:
6d40c4a7 4880 error = receive_unlock(ls, ms);
e7fd4179
DT		 4881 break;
4882
4883 case DLM_MSG_CANCEL:
6d40c4a7
DT		 4884 noent = 1;
4885 error = receive_cancel(ls, ms);
e7fd4179
DT		 4886 break;
4887
4888 /* messages sent from a master node (replies to above) */
4889
4890 case DLM_MSG_REQUEST_REPLY:
6d40c4a7 4891 error = receive_request_reply(ls, ms);
e7fd4179
DT		 4892 break;
4893
4894 case DLM_MSG_CONVERT_REPLY:
6d40c4a7 4895 error = receive_convert_reply(ls, ms);
e7fd4179
DT		 4896 break;
4897
4898 case DLM_MSG_UNLOCK_REPLY:
6d40c4a7 4899 error = receive_unlock_reply(ls, ms);
e7fd4179
DT		 4900 break;
4901
4902 case DLM_MSG_CANCEL_REPLY:
6d40c4a7 4903 error = receive_cancel_reply(ls, ms);
e7fd4179
DT		 4904 break;
4905
4906 /* messages sent from a master node (only two types of async msg) */
4907
4908 case DLM_MSG_GRANT:
6d40c4a7
DT		 4909 noent = 1;
4910 error = receive_grant(ls, ms);
e7fd4179
DT		 4911 break;
4912
4913 case DLM_MSG_BAST:
6d40c4a7
DT		 4914 noent = 1;
4915 error = receive_bast(ls, ms);
e7fd4179
DT		 4916 break;
4917
4918 /* messages sent to a dir node */
4919
4920 case DLM_MSG_LOOKUP:
4921 receive_lookup(ls, ms);
4922 break;
4923
4924 case DLM_MSG_REMOVE:
4925 receive_remove(ls, ms);
4926 break;
4927
4928 /* messages sent from a dir node (remove has no reply) */
4929
4930 case DLM_MSG_LOOKUP_REPLY:
4931 receive_lookup_reply(ls, ms);
4932 break;
4933
8499137d
DT		 4934 /* other messages */
4935
4936 case DLM_MSG_PURGE:
4937 receive_purge(ls, ms);
4938 break;
4939
e7fd4179
DT		 4940 default:
4941 log_error(ls, "unknown message type %d", ms->m_type);
4942 }
6d40c4a7
DT		 4943
4944 /*
4945 * When checking for ENOENT, we're checking the result of
4946 * find_lkb(m_remid):
4947 *
4948 * The lock id referenced in the message wasn't found. This may
4949 * happen in normal usage for the async messages and cancel, so
4950 * only use log_debug for them.
4951 *
4875647a 4952 * Some errors are expected and normal.
6d40c4a7
DT		 4953 */
4954
4955 if (error == -ENOENT && noent) {
4875647a 4956 log_debug(ls, "receive %d no %x remote %d %x saved_seq %u",
6d40c4a7
DT		 4957 ms->m_type, ms->m_remid, ms->m_header.h_nodeid,
4958 ms->m_lkid, saved_seq);
4959 } else if (error == -ENOENT) {
4875647a 4960 log_error(ls, "receive %d no %x remote %d %x saved_seq %u",
6d40c4a7
DT		 4961 ms->m_type, ms->m_remid, ms->m_header.h_nodeid,
4962 ms->m_lkid, saved_seq);
4963
4964 if (ms->m_type == DLM_MSG_CONVERT)
4965 dlm_dump_rsb_hash(ls, ms->m_hash);
4966 }
4875647a
DT		 4967
4968 if (error == -EINVAL) {
4969 log_error(ls, "receive %d inval from %d lkid %x remid %x "
4970 "saved_seq %u",
4971 ms->m_type, ms->m_header.h_nodeid,
4972 ms->m_lkid, ms->m_remid, saved_seq);
4973 }
e7fd4179
DT		 4974}
4975
c36258b5
DT		 4976/* If the lockspace is in recovery mode (locking stopped), then normal
4977 messages are saved on the requestqueue for processing after recovery is
4978 done. When not in recovery mode, we wait for dlm_recoverd to drain saved
4979 messages off the requestqueue before we process new ones. This occurs right
4980 after recovery completes when we transition from saving all messages on
4981 requestqueue, to processing all the saved messages, to processing new
4982 messages as they arrive. */
e7fd4179 4983
c36258b5
DT		 4984static void dlm_receive_message(struct dlm_ls *ls, struct dlm_message *ms,
4985 int nodeid)
4986{
4987 if (dlm_locking_stopped(ls)) {
c04fecb4
DT		 4988 /* If we were a member of this lockspace, left, and rejoined,
4989 other nodes may still be sending us messages from the
4990 lockspace generation before we left. */
4991 if (!ls->ls_generation) {
4992 log_limit(ls, "receive %d from %d ignore old gen",
4993 ms->m_type, nodeid);
4994 return;
4995 }
4996
8b0d8e03 4997 dlm_add_requestqueue(ls, nodeid, ms);
c36258b5
DT		 4998 } else {
4999 dlm_wait_requestqueue(ls);
6d40c4a7 5000 _receive_message(ls, ms, 0);
c36258b5
DT		 5001 }
5002}
5003
5004/* This is called by dlm_recoverd to process messages that were saved on
5005 the requestqueue. */
5006
6d40c4a7
DT		 5007void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms,
5008 uint32_t saved_seq)
c36258b5 5009{
6d40c4a7 5010 _receive_message(ls, ms, saved_seq);
c36258b5
DT		 5011}
5012
5013/* This is called by the midcomms layer when something is received for
5014 the lockspace. It could be either a MSG (normal message sent as part of
5015 standard locking activity) or an RCOM (recovery message sent as part of
5016 lockspace recovery). */
5017
eef7d739 5018void dlm_receive_buffer(union dlm_packet *p, int nodeid)
c36258b5 5019{
eef7d739 5020 struct dlm_header *hd = &p->header;
c36258b5
DT		 5021 struct dlm_ls *ls;
5022 int type = 0;
5023
5024 switch (hd->h_cmd) {
5025 case DLM_MSG:
eef7d739
AV		 5026 dlm_message_in(&p->message);
5027 type = p->message.m_type;
c36258b5
DT		 5028 break;
5029 case DLM_RCOM:
eef7d739
AV		 5030 dlm_rcom_in(&p->rcom);
5031 type = p->rcom.rc_type;
c36258b5
DT		 5032 break;
5033 default:
5034 log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
5035 return;
5036 }
5037
5038 if (hd->h_nodeid != nodeid) {
5039 log_print("invalid h_nodeid %d from %d lockspace %x",
5040 hd->h_nodeid, nodeid, hd->h_lockspace);
5041 return;
5042 }
5043
5044 ls = dlm_find_lockspace_global(hd->h_lockspace);
5045 if (!ls) {
4875647a
DT		 5046 if (dlm_config.ci_log_debug) {
5047 printk_ratelimited(KERN_DEBUG "dlm: invalid lockspace "
5048 "%u from %d cmd %d type %d\n",
5049 hd->h_lockspace, nodeid, hd->h_cmd, type);
5050 }
c36258b5
DT		 5051
5052 if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
eef7d739 5053 dlm_send_ls_not_ready(nodeid, &p->rcom);
c36258b5
DT		 5054 return;
5055 }
5056
5057 /* this rwsem allows dlm_ls_stop() to wait for all dlm_recv threads to
5058 be inactive (in this ls) before transitioning to recovery mode */
5059
5060 down_read(&ls->ls_recv_active);
5061 if (hd->h_cmd == DLM_MSG)
eef7d739 5062 dlm_receive_message(ls, &p->message, nodeid);
c36258b5 5063 else
eef7d739 5064 dlm_receive_rcom(ls, &p->rcom, nodeid);
c36258b5
DT		 5065 up_read(&ls->ls_recv_active);
5066
5067 dlm_put_lockspace(ls);
5068}
e7fd4179 5069
2a7ce0ed
DT		 5070static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb,
5071 struct dlm_message *ms_stub)
e7fd4179
DT		 5072{
5073 if (middle_conversion(lkb)) {
5074 hold_lkb(lkb);
2a7ce0ed
DT		 5075 memset(ms_stub, 0, sizeof(struct dlm_message));
5076 ms_stub->m_flags = DLM_IFL_STUB_MS;
5077 ms_stub->m_type = DLM_MSG_CONVERT_REPLY;
5078 ms_stub->m_result = -EINPROGRESS;
5079 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5080 _receive_convert_reply(lkb, ms_stub);
e7fd4179
DT		 5081
5082 /* Same special case as in receive_rcom_lock_args() */
5083 lkb->lkb_grmode = DLM_LOCK_IV;
5084 rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT);
5085 unhold_lkb(lkb);
5086
5087 } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) {
5088 lkb->lkb_flags |= DLM_IFL_RESEND;
5089 }
5090
5091 /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down
5092 conversions are async; there's no reply from the remote master */
5093}
5094
5095/* A waiting lkb needs recovery if the master node has failed, or
5096 the master node is changing (only when no directory is used) */
5097
13ef1111
DT		 5098static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb,
5099 int dir_nodeid)
e7fd4179 5100{
4875647a 5101 if (dlm_no_directory(ls))
13ef1111
DT		 5102 return 1;
5103
4875647a 5104 if (dlm_is_removed(ls, lkb->lkb_wait_nodeid))
e7fd4179
DT		 5105 return 1;
5106
5107 return 0;
5108}
5109
5110/* Recovery for locks that are waiting for replies from nodes that are now
5111 gone. We can just complete unlocks and cancels by faking a reply from the
5112 dead node. Requests and up-conversions we flag to be resent after
5113 recovery. Down-conversions can just be completed with a fake reply like
5114 unlocks. Conversions between PR and CW need special attention. */
5115
5116void dlm_recover_waiters_pre(struct dlm_ls *ls)
5117{
5118 struct dlm_lkb *lkb, *safe;
2a7ce0ed 5119 struct dlm_message *ms_stub;
601342ce 5120 int wait_type, stub_unlock_result, stub_cancel_result;
13ef1111 5121 int dir_nodeid;
e7fd4179 5122
a22ca480 5123 ms_stub = kmalloc(sizeof(struct dlm_message), GFP_KERNEL);
2a7ce0ed
DT		 5124 if (!ms_stub) {
5125 log_error(ls, "dlm_recover_waiters_pre no mem");
5126 return;
5127 }
5128
90135925 5129 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 5130
5131 list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) {
2a7ce0ed 5132
13ef1111
DT		 5133 dir_nodeid = dlm_dir_nodeid(lkb->lkb_resource);
5134
2a7ce0ed
DT		 5135 /* exclude debug messages about unlocks because there can be so
5136 many and they aren't very interesting */
5137
5138 if (lkb->lkb_wait_type != DLM_MSG_UNLOCK) {
13ef1111
DT		 5139 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5140 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d",
5141 lkb->lkb_id,
5142 lkb->lkb_remid,
5143 lkb->lkb_wait_type,
5144 lkb->lkb_resource->res_nodeid,
5145 lkb->lkb_nodeid,
5146 lkb->lkb_wait_nodeid,
5147 dir_nodeid);
2a7ce0ed 5148 }
e7fd4179
DT		 5149
5150 /* all outstanding lookups, regardless of destination will be
5151 resent after recovery is done */
5152
5153 if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) {
5154 lkb->lkb_flags |= DLM_IFL_RESEND;
5155 continue;
5156 }
5157
13ef1111 5158 if (!waiter_needs_recovery(ls, lkb, dir_nodeid))
e7fd4179
DT		 5159 continue;
5160
601342ce
DT		 5161 wait_type = lkb->lkb_wait_type;
5162 stub_unlock_result = -DLM_EUNLOCK;
5163 stub_cancel_result = -DLM_ECANCEL;
5164
5165 /* Main reply may have been received leaving a zero wait_type,
5166 but a reply for the overlapping op may not have been
5167 received. In that case we need to fake the appropriate
5168 reply for the overlap op. */
5169
5170 if (!wait_type) {
5171 if (is_overlap_cancel(lkb)) {
5172 wait_type = DLM_MSG_CANCEL;
5173 if (lkb->lkb_grmode == DLM_LOCK_IV)
5174 stub_cancel_result = 0;
5175 }
5176 if (is_overlap_unlock(lkb)) {
5177 wait_type = DLM_MSG_UNLOCK;
5178 if (lkb->lkb_grmode == DLM_LOCK_IV)
5179 stub_unlock_result = -ENOENT;
5180 }
5181
5182 log_debug(ls, "rwpre overlap %x %x %d %d %d",
5183 lkb->lkb_id, lkb->lkb_flags, wait_type,
5184 stub_cancel_result, stub_unlock_result);
5185 }
5186
5187 switch (wait_type) {
e7fd4179
DT		 5188
5189 case DLM_MSG_REQUEST:
5190 lkb->lkb_flags |= DLM_IFL_RESEND;
5191 break;
5192
5193 case DLM_MSG_CONVERT:
2a7ce0ed 5194 recover_convert_waiter(ls, lkb, ms_stub);
e7fd4179
DT		 5195 break;
5196
5197 case DLM_MSG_UNLOCK:
5198 hold_lkb(lkb);
2a7ce0ed
DT		 5199 memset(ms_stub, 0, sizeof(struct dlm_message));
5200 ms_stub->m_flags = DLM_IFL_STUB_MS;
5201 ms_stub->m_type = DLM_MSG_UNLOCK_REPLY;
5202 ms_stub->m_result = stub_unlock_result;
5203 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5204 _receive_unlock_reply(lkb, ms_stub);
b3f58d8f 5205 dlm_put_lkb(lkb);
e7fd4179
DT		 5206 break;
5207
5208 case DLM_MSG_CANCEL:
5209 hold_lkb(lkb);
2a7ce0ed
DT		 5210 memset(ms_stub, 0, sizeof(struct dlm_message));
5211 ms_stub->m_flags = DLM_IFL_STUB_MS;
5212 ms_stub->m_type = DLM_MSG_CANCEL_REPLY;
5213 ms_stub->m_result = stub_cancel_result;
5214 ms_stub->m_header.h_nodeid = lkb->lkb_nodeid;
5215 _receive_cancel_reply(lkb, ms_stub);
b3f58d8f 5216 dlm_put_lkb(lkb);
e7fd4179
DT		 5217 break;
5218
5219 default:
601342ce
DT		 5220 log_error(ls, "invalid lkb wait_type %d %d",
5221 lkb->lkb_wait_type, wait_type);
e7fd4179 5222 }
81456807 5223 schedule();
e7fd4179 5224 }
90135925 5225 mutex_unlock(&ls->ls_waiters_mutex);
2a7ce0ed 5226 kfree(ms_stub);
e7fd4179
DT		 5227}
5228
ef0c2bb0 5229static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls)
e7fd4179
DT		 5230{
5231 struct dlm_lkb *lkb;
ef0c2bb0 5232 int found = 0;
e7fd4179 5233
90135925 5234 mutex_lock(&ls->ls_waiters_mutex);
e7fd4179
DT		 5235 list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
5236 if (lkb->lkb_flags & DLM_IFL_RESEND) {
ef0c2bb0
DT		 5237 hold_lkb(lkb);
5238 found = 1;
e7fd4179
DT		 5239 break;
5240 }
5241 }
90135925 5242 mutex_unlock(&ls->ls_waiters_mutex);
e7fd4179 5243
ef0c2bb0 5244 if (!found)
e7fd4179 5245 lkb = NULL;
ef0c2bb0 5246 return lkb;
e7fd4179
DT		 5247}
5248
5249/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the
5250 master or dir-node for r. Processing the lkb may result in it being placed
5251 back on waiters. */
5252
ef0c2bb0
DT		 5253/* We do this after normal locking has been enabled and any saved messages
5254 (in requestqueue) have been processed. We should be confident that at
5255 this point we won't get or process a reply to any of these waiting
5256 operations. But, new ops may be coming in on the rsbs/locks here from
5257 userspace or remotely. */
5258
5259/* there may have been an overlap unlock/cancel prior to recovery or after
5260 recovery. if before, the lkb may still have a pos wait_count; if after, the
5261 overlap flag would just have been set and nothing new sent. we can be
5262 confident here than any replies to either the initial op or overlap ops
5263 prior to recovery have been received. */
5264
e7fd4179
DT		 5265int dlm_recover_waiters_post(struct dlm_ls *ls)
5266{
5267 struct dlm_lkb *lkb;
5268 struct dlm_rsb *r;
ef0c2bb0 5269 int error = 0, mstype, err, oc, ou;
e7fd4179
DT		 5270
5271 while (1) {
5272 if (dlm_locking_stopped(ls)) {
5273 log_debug(ls, "recover_waiters_post aborted");
5274 error = -EINTR;
5275 break;
5276 }
5277
ef0c2bb0
DT		 5278 lkb = find_resend_waiter(ls);
5279 if (!lkb)
e7fd4179
DT		 5280 break;
5281
5282 r = lkb->lkb_resource;
ef0c2bb0
DT		 5283 hold_rsb(r);
5284 lock_rsb(r);
5285
5286 mstype = lkb->lkb_wait_type;
5287 oc = is_overlap_cancel(lkb);
5288 ou = is_overlap_unlock(lkb);
5289 err = 0;
e7fd4179 5290
13ef1111
DT		 5291 log_debug(ls, "waiter %x remote %x msg %d r_nodeid %d "
5292 "lkb_nodeid %d wait_nodeid %d dir_nodeid %d "
5293 "overlap %d %d", lkb->lkb_id, lkb->lkb_remid, mstype,
5294 r->res_nodeid, lkb->lkb_nodeid, lkb->lkb_wait_nodeid,
5295 dlm_dir_nodeid(r), oc, ou);
e7fd4179 5296
ef0c2bb0
DT		 5297 /* At this point we assume that we won't get a reply to any
5298 previous op or overlap op on this lock. First, do a big
5299 remove_from_waiters() for all previous ops. */
5300
5301 lkb->lkb_flags &= ~DLM_IFL_RESEND;
5302 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_UNLOCK;
5303 lkb->lkb_flags &= ~DLM_IFL_OVERLAP_CANCEL;
5304 lkb->lkb_wait_type = 0;
5305 lkb->lkb_wait_count = 0;
5306 mutex_lock(&ls->ls_waiters_mutex);
5307 list_del_init(&lkb->lkb_wait_reply);
5308 mutex_unlock(&ls->ls_waiters_mutex);
5309 unhold_lkb(lkb); /* for waiters list */
5310
5311 if (oc || ou) {
5312 /* do an unlock or cancel instead of resending */
5313 switch (mstype) {
5314 case DLM_MSG_LOOKUP:
5315 case DLM_MSG_REQUEST:
5316 queue_cast(r, lkb, ou ? -DLM_EUNLOCK :
5317 -DLM_ECANCEL);
5318 unhold_lkb(lkb); /* undoes create_lkb() */
5319 break;
5320 case DLM_MSG_CONVERT:
5321 if (oc) {
5322 queue_cast(r, lkb, -DLM_ECANCEL);
5323 } else {
5324 lkb->lkb_exflags |= DLM_LKF_FORCEUNLOCK;
5325 _unlock_lock(r, lkb);
5326 }
5327 break;
5328 default:
5329 err = 1;
5330 }
5331 } else {
5332 switch (mstype) {
5333 case DLM_MSG_LOOKUP:
5334 case DLM_MSG_REQUEST:
5335 _request_lock(r, lkb);
5336 if (is_master(r))
5337 confirm_master(r, 0);
5338 break;
5339 case DLM_MSG_CONVERT:
5340 _convert_lock(r, lkb);
5341 break;
5342 default:
5343 err = 1;
5344 }
e7fd4179 5345 }
ef0c2bb0 5346
13ef1111
DT		 5347 if (err) {
5348 log_error(ls, "waiter %x msg %d r_nodeid %d "
5349 "dir_nodeid %d overlap %d %d",
5350 lkb->lkb_id, mstype, r->res_nodeid,
5351 dlm_dir_nodeid(r), oc, ou);
5352 }
ef0c2bb0
DT		 5353 unlock_rsb(r);
5354 put_rsb(r);
5355 dlm_put_lkb(lkb);
e7fd4179
DT		 5356 }
5357
5358 return error;
5359}
5360
4875647a
DT		 5361static void purge_mstcpy_list(struct dlm_ls *ls, struct dlm_rsb *r,
5362 struct list_head *list)
e7fd4179 5363{
e7fd4179
DT		 5364 struct dlm_lkb *lkb, *safe;
5365
4875647a
DT		 5366 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5367 if (!is_master_copy(lkb))
5368 continue;
5369
5370 /* don't purge lkbs we've added in recover_master_copy for
5371 the current recovery seq */
5372
5373 if (lkb->lkb_recover_seq == ls->ls_recover_seq)
5374 continue;
5375
5376 del_lkb(r, lkb);
5377
5378 /* this put should free the lkb */
5379 if (!dlm_put_lkb(lkb))
5380 log_error(ls, "purged mstcpy lkb not released");
e7fd4179
DT		 5381 }
5382}
5383
4875647a 5384void dlm_purge_mstcpy_locks(struct dlm_rsb *r)
e7fd4179 5385{
4875647a 5386 struct dlm_ls *ls = r->res_ls;
e7fd4179 5387
4875647a
DT		 5388 purge_mstcpy_list(ls, r, &r->res_grantqueue);
5389 purge_mstcpy_list(ls, r, &r->res_convertqueue);
5390 purge_mstcpy_list(ls, r, &r->res_waitqueue);
e7fd4179
DT		 5391}
5392
4875647a
DT		 5393static void purge_dead_list(struct dlm_ls *ls, struct dlm_rsb *r,
5394 struct list_head *list,
5395 int nodeid_gone, unsigned int *count)
e7fd4179 5396{
4875647a 5397 struct dlm_lkb *lkb, *safe;
e7fd4179 5398
4875647a
DT		 5399 list_for_each_entry_safe(lkb, safe, list, lkb_statequeue) {
5400 if (!is_master_copy(lkb))
5401 continue;
5402
5403 if ((lkb->lkb_nodeid == nodeid_gone) ||
5404 dlm_is_removed(ls, lkb->lkb_nodeid)) {
5405
da8c6663
DT		 5406 /* tell recover_lvb to invalidate the lvb
5407 because a node holding EX/PW failed */
5408 if ((lkb->lkb_exflags & DLM_LKF_VALBLK) &&
5409 (lkb->lkb_grmode >= DLM_LOCK_PW)) {
5410 rsb_set_flag(r, RSB_RECOVER_LVB_INVAL);
5411 }
5412
4875647a
DT		 5413 del_lkb(r, lkb);
5414
5415 /* this put should free the lkb */
5416 if (!dlm_put_lkb(lkb))
5417 log_error(ls, "purged dead lkb not released");
5418
5419 rsb_set_flag(r, RSB_RECOVER_GRANT);
5420
5421 (*count)++;
5422 }
5423 }
e7fd4179
DT		 5424}
5425
5426/* Get rid of locks held by nodes that are gone. */
5427
4875647a 5428void dlm_recover_purge(struct dlm_ls *ls)
e7fd4179
DT		 5429{
5430 struct dlm_rsb *r;
4875647a
DT		 5431 struct dlm_member *memb;
5432 int nodes_count = 0;
5433 int nodeid_gone = 0;
5434 unsigned int lkb_count = 0;
5435
5436 /* cache one removed nodeid to optimize the common
5437 case of a single node removed */
5438
5439 list_for_each_entry(memb, &ls->ls_nodes_gone, list) {
5440 nodes_count++;
5441 nodeid_gone = memb->nodeid;
5442 }
e7fd4179 5443
4875647a
DT		 5444 if (!nodes_count)
5445 return;
e7fd4179
DT		 5446
5447 down_write(&ls->ls_root_sem);
5448 list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
5449 hold_rsb(r);
5450 lock_rsb(r);
4875647a
DT		 5451 if (is_master(r)) {
5452 purge_dead_list(ls, r, &r->res_grantqueue,
5453 nodeid_gone, &lkb_count);
5454 purge_dead_list(ls, r, &r->res_convertqueue,
5455 nodeid_gone, &lkb_count);
5456 purge_dead_list(ls, r, &r->res_waitqueue,
5457 nodeid_gone, &lkb_count);
5458 }
e7fd4179
DT		 5459 unlock_rsb(r);
5460 unhold_rsb(r);
4875647a 5461 cond_resched();
e7fd4179
DT		 5462 }
5463 up_write(&ls->ls_root_sem);
5464
4875647a 5465 if (lkb_count)
075f0177 5466 log_rinfo(ls, "dlm_recover_purge %u locks for %u nodes",
4875647a 5467 lkb_count, nodes_count);
e7fd4179
DT		 5468}
5469
4875647a 5470static struct dlm_rsb *find_grant_rsb(struct dlm_ls *ls, int bucket)
97a35d1e 5471{
9beb3bf5 5472 struct rb_node *n;
4875647a 5473 struct dlm_rsb *r;
97a35d1e 5474
c7be761a 5475 spin_lock(&ls->ls_rsbtbl[bucket].lock);
9beb3bf5
BP		 5476 for (n = rb_first(&ls->ls_rsbtbl[bucket].keep); n; n = rb_next(n)) {
5477 r = rb_entry(n, struct dlm_rsb, res_hashnode);
4875647a
DT		 5478
5479 if (!rsb_flag(r, RSB_RECOVER_GRANT))
5480 continue;
c503a621
DT		 5481 if (!is_master(r)) {
5482 rsb_clear_flag(r, RSB_RECOVER_GRANT);
97a35d1e 5483 continue;
c503a621 5484 }
97a35d1e 5485 hold_rsb(r);
4875647a
DT		 5486 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
5487 return r;
97a35d1e 5488 }
c7be761a 5489 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
4875647a 5490 return NULL;
97a35d1e
DT		 5491}
5492
4875647a
DT		 5493/*
5494 * Attempt to grant locks on resources that we are the master of.
5495 * Locks may have become grantable during recovery because locks
5496 * from departed nodes have been purged (or not rebuilt), allowing
5497 * previously blocked locks to now be granted. The subset of rsb's
5498 * we are interested in are those with lkb's on either the convert or
5499 * waiting queues.
5500 *
5501 * Simplest would be to go through each master rsb and check for non-empty
5502 * convert or waiting queues, and attempt to grant on those rsbs.
5503 * Checking the queues requires lock_rsb, though, for which we'd need
5504 * to release the rsbtbl lock. This would make iterating through all
5505 * rsb's very inefficient. So, we rely on earlier recovery routines
5506 * to set RECOVER_GRANT on any rsb's that we should attempt to grant
5507 * locks for.
5508 */
5509
5510void dlm_recover_grant(struct dlm_ls *ls)
e7fd4179
DT		 5511{
5512 struct dlm_rsb *r;
2b4e926a 5513 int bucket = 0;
4875647a
DT		 5514 unsigned int count = 0;
5515 unsigned int rsb_count = 0;
5516 unsigned int lkb_count = 0;
e7fd4179 5517
2b4e926a 5518 while (1) {
4875647a 5519 r = find_grant_rsb(ls, bucket);
2b4e926a
DT		 5520 if (!r) {
5521 if (bucket == ls->ls_rsbtbl_size - 1)
5522 break;
5523 bucket++;
97a35d1e 5524 continue;
2b4e926a 5525 }
4875647a
DT		 5526 rsb_count++;
5527 count = 0;
97a35d1e 5528 lock_rsb(r);
c503a621 5529 /* the RECOVER_GRANT flag is checked in the grant path */
4875647a 5530 grant_pending_locks(r, &count);
c503a621 5531 rsb_clear_flag(r, RSB_RECOVER_GRANT);
4875647a
DT		 5532 lkb_count += count;
5533 confirm_master(r, 0);
97a35d1e
DT		 5534 unlock_rsb(r);
5535 put_rsb(r);
4875647a 5536 cond_resched();
e7fd4179 5537 }
4875647a
DT		 5538
5539 if (lkb_count)
075f0177 5540 log_rinfo(ls, "dlm_recover_grant %u locks on %u resources",
4875647a 5541 lkb_count, rsb_count);
e7fd4179
DT		 5542}
5543
5544static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid,
5545 uint32_t remid)
5546{
5547 struct dlm_lkb *lkb;
5548
5549 list_for_each_entry(lkb, head, lkb_statequeue) {
5550 if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid)
5551 return lkb;
5552 }
5553 return NULL;
5554}
5555
5556static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
5557 uint32_t remid)
5558{
5559 struct dlm_lkb *lkb;
5560
5561 lkb = search_remid_list(&r->res_grantqueue, nodeid, remid);
5562 if (lkb)
5563 return lkb;
5564 lkb = search_remid_list(&r->res_convertqueue, nodeid, remid);
5565 if (lkb)
5566 return lkb;
5567 lkb = search_remid_list(&r->res_waitqueue, nodeid, remid);
5568 if (lkb)
5569 return lkb;
5570 return NULL;
5571}
5572
ae773d0b 5573/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 5574static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
5575 struct dlm_rsb *r, struct dlm_rcom *rc)
5576{
5577 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
e7fd4179
DT		 5578
5579 lkb->lkb_nodeid = rc->rc_header.h_nodeid;
163a1859
AV		 5580 lkb->lkb_ownpid = le32_to_cpu(rl->rl_ownpid);
5581 lkb->lkb_remid = le32_to_cpu(rl->rl_lkid);
5582 lkb->lkb_exflags = le32_to_cpu(rl->rl_exflags);
5583 lkb->lkb_flags = le32_to_cpu(rl->rl_flags) & 0x0000FFFF;
e7fd4179 5584 lkb->lkb_flags |= DLM_IFL_MSTCPY;
163a1859 5585 lkb->lkb_lvbseq = le32_to_cpu(rl->rl_lvbseq);
e7fd4179
DT		 5586 lkb->lkb_rqmode = rl->rl_rqmode;
5587 lkb->lkb_grmode = rl->rl_grmode;
5588 /* don't set lkb_status because add_lkb wants to itself */
5589
8304d6f2
DT		 5590 lkb->lkb_bastfn = (rl->rl_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
5591 lkb->lkb_astfn = (rl->rl_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
e7fd4179 5592
e7fd4179 5593 if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
a5dd0631
AV		 5594 int lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) -
5595 sizeof(struct rcom_lock);
5596 if (lvblen > ls->ls_lvblen)
5597 return -EINVAL;
52bda2b5 5598 lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
e7fd4179
DT		 5599 if (!lkb->lkb_lvbptr)
5600 return -ENOMEM;
e7fd4179
DT		 5601 memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen);
5602 }
5603
5604 /* Conversions between PR and CW (middle modes) need special handling.
5605 The real granted mode of these converting locks cannot be determined
5606 until all locks have been rebuilt on the rsb (recover_conversion) */
5607
163a1859
AV		 5608 if (rl->rl_wait_type == cpu_to_le16(DLM_MSG_CONVERT) &&
5609 middle_conversion(lkb)) {
e7fd4179
DT		 5610 rl->rl_status = DLM_LKSTS_CONVERT;
5611 lkb->lkb_grmode = DLM_LOCK_IV;
5612 rsb_set_flag(r, RSB_RECOVER_CONVERT);
5613 }
5614
5615 return 0;
5616}
5617
5618/* This lkb may have been recovered in a previous aborted recovery so we need
5619 to check if the rsb already has an lkb with the given remote nodeid/lkid.
5620 If so we just send back a standard reply. If not, we create a new lkb with
5621 the given values and send back our lkid. We send back our lkid by sending
5622 back the rcom_lock struct we got but with the remid field filled in. */
5623
ae773d0b 5624/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 5625int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
5626{
5627 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5628 struct dlm_rsb *r;
5629 struct dlm_lkb *lkb;
6d40c4a7 5630 uint32_t remid = 0;
c04fecb4 5631 int from_nodeid = rc->rc_header.h_nodeid;
e7fd4179
DT		 5632 int error;
5633
5634 if (rl->rl_parent_lkid) {
5635 error = -EOPNOTSUPP;
5636 goto out;
5637 }
5638
6d40c4a7
DT		 5639 remid = le32_to_cpu(rl->rl_lkid);
5640
4875647a
DT		 5641 /* In general we expect the rsb returned to be R_MASTER, but we don't
5642 have to require it. Recovery of masters on one node can overlap
5643 recovery of locks on another node, so one node can send us MSTCPY
5644 locks before we've made ourselves master of this rsb. We can still
5645 add new MSTCPY locks that we receive here without any harm; when
5646 we make ourselves master, dlm_recover_masters() won't touch the
5647 MSTCPY locks we've received early. */
5648
c04fecb4
DT		 5649 error = find_rsb(ls, rl->rl_name, le16_to_cpu(rl->rl_namelen),
5650 from_nodeid, R_RECEIVE_RECOVER, &r);
e7fd4179
DT		 5651 if (error)
5652 goto out;
5653
c04fecb4
DT		 5654 lock_rsb(r);
5655
4875647a
DT		 5656 if (dlm_no_directory(ls) && (dlm_dir_nodeid(r) != dlm_our_nodeid())) {
5657 log_error(ls, "dlm_recover_master_copy remote %d %x not dir",
c04fecb4 5658 from_nodeid, remid);
4875647a 5659 error = -EBADR;
c04fecb4 5660 goto out_unlock;
4875647a
DT		 5661 }
5662
c04fecb4 5663 lkb = search_remid(r, from_nodeid, remid);
e7fd4179
DT		 5664 if (lkb) {
5665 error = -EEXIST;
5666 goto out_remid;
5667 }
5668
5669 error = create_lkb(ls, &lkb);
5670 if (error)
5671 goto out_unlock;
5672
5673 error = receive_rcom_lock_args(ls, lkb, r, rc);
5674 if (error) {
b3f58d8f 5675 __put_lkb(ls, lkb);
e7fd4179
DT		 5676 goto out_unlock;
5677 }
5678
5679 attach_lkb(r, lkb);
5680 add_lkb(r, lkb, rl->rl_status);
5681 error = 0;
4875647a
DT		 5682 ls->ls_recover_locks_in++;
5683
5684 if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue))
5685 rsb_set_flag(r, RSB_RECOVER_GRANT);
e7fd4179
DT		 5686
5687 out_remid:
5688 /* this is the new value returned to the lock holder for
5689 saving in its process-copy lkb */
163a1859 5690 rl->rl_remid = cpu_to_le32(lkb->lkb_id);
e7fd4179 5691
4875647a
DT		 5692 lkb->lkb_recover_seq = ls->ls_recover_seq;
5693
e7fd4179
DT		 5694 out_unlock:
5695 unlock_rsb(r);
5696 put_rsb(r);
5697 out:
6d40c4a7 5698 if (error && error != -EEXIST)
075f0177 5699 log_rinfo(ls, "dlm_recover_master_copy remote %d %x error %d",
c04fecb4 5700 from_nodeid, remid, error);
163a1859 5701 rl->rl_result = cpu_to_le32(error);
e7fd4179
DT		 5702 return error;
5703}
5704
ae773d0b 5705/* needs at least dlm_rcom + rcom_lock */
e7fd4179
DT		 5706int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
5707{
5708 struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
5709 struct dlm_rsb *r;
5710 struct dlm_lkb *lkb;
6d40c4a7
DT		 5711 uint32_t lkid, remid;
5712 int error, result;
5713
5714 lkid = le32_to_cpu(rl->rl_lkid);
5715 remid = le32_to_cpu(rl->rl_remid);
5716 result = le32_to_cpu(rl->rl_result);
e7fd4179 5717
6d40c4a7 5718 error = find_lkb(ls, lkid, &lkb);
e7fd4179 5719 if (error) {
6d40c4a7
DT		 5720 log_error(ls, "dlm_recover_process_copy no %x remote %d %x %d",
5721 lkid, rc->rc_header.h_nodeid, remid, result);
e7fd4179
DT		 5722 return error;
5723 }
5724
4875647a
DT		 5725 r = lkb->lkb_resource;
5726 hold_rsb(r);
5727 lock_rsb(r);
5728
6d40c4a7
DT		 5729 if (!is_process_copy(lkb)) {
5730 log_error(ls, "dlm_recover_process_copy bad %x remote %d %x %d",
5731 lkid, rc->rc_header.h_nodeid, remid, result);
4875647a
DT		 5732 dlm_dump_rsb(r);
5733 unlock_rsb(r);
5734 put_rsb(r);
5735 dlm_put_lkb(lkb);
6d40c4a7
DT		 5736 return -EINVAL;
5737 }
e7fd4179 5738
6d40c4a7 5739 switch (result) {
dc200a88
DT		 5740 case -EBADR:
5741 /* There's a chance the new master received our lock before
5742 dlm_recover_master_reply(), this wouldn't happen if we did
5743 a barrier between recover_masters and recover_locks. */
6d40c4a7
DT		 5744
5745 log_debug(ls, "dlm_recover_process_copy %x remote %d %x %d",
5746 lkid, rc->rc_header.h_nodeid, remid, result);
5747
dc200a88
DT		 5748 dlm_send_rcom_lock(r, lkb);
5749 goto out;
e7fd4179 5750 case -EEXIST:
e7fd4179 5751 case 0:
6d40c4a7 5752 lkb->lkb_remid = remid;
e7fd4179
DT		 5753 break;
5754 default:
6d40c4a7
DT		 5755 log_error(ls, "dlm_recover_process_copy %x remote %d %x %d unk",
5756 lkid, rc->rc_header.h_nodeid, remid, result);
e7fd4179
DT		 5757 }
5758
5759 /* an ack for dlm_recover_locks() which waits for replies from
5760 all the locks it sends to new masters */
5761 dlm_recovered_lock(r);
dc200a88 5762 out:
e7fd4179
DT		 5763 unlock_rsb(r);
5764 put_rsb(r);
b3f58d8f 5765 dlm_put_lkb(lkb);
e7fd4179
DT		 5766
5767 return 0;
5768}
5769
597d0cae
DT		 5770int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
5771 int mode, uint32_t flags, void *name, unsigned int namelen,
d7db923e 5772 unsigned long timeout_cs)
597d0cae
DT		 5773{
5774 struct dlm_lkb *lkb;
5775 struct dlm_args args;
5776 int error;
5777
85e86edf 5778 dlm_lock_recovery(ls);
597d0cae
DT		 5779
5780 error = create_lkb(ls, &lkb);
5781 if (error) {
5782 kfree(ua);
5783 goto out;
5784 }
5785
5786 if (flags & DLM_LKF_VALBLK) {
573c24c4 5787 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
597d0cae
DT		 5788 if (!ua->lksb.sb_lvbptr) {
5789 kfree(ua);
5790 __put_lkb(ls, lkb);
5791 error = -ENOMEM;
5792 goto out;
5793 }
5794 }
5795
52bda2b5 5796 /* After ua is attached to lkb it will be freed by dlm_free_lkb().
597d0cae
DT		 5797 When DLM_IFL_USER is set, the dlm knows that this is a userspace
5798 lock and that lkb_astparam is the dlm_user_args structure. */
5799
d7db923e 5800 error = set_lock_args(mode, &ua->lksb, flags, namelen, timeout_cs,
e5dae548 5801 fake_astfn, ua, fake_bastfn, &args);
597d0cae 5802 lkb->lkb_flags |= DLM_IFL_USER;
597d0cae
DT		 5803
5804 if (error) {
5805 __put_lkb(ls, lkb);
5806 goto out;
5807 }
5808
5809 error = request_lock(ls, lkb, name, namelen, &args);
5810
5811 switch (error) {
5812 case 0:
5813 break;
5814 case -EINPROGRESS:
5815 error = 0;
5816 break;
5817 case -EAGAIN:
5818 error = 0;
5819 /* fall through */
5820 default:
5821 __put_lkb(ls, lkb);
5822 goto out;
5823 }
5824
5825 /* add this new lkb to the per-process list of locks */
5826 spin_lock(&ua->proc->locks_spin);
ef0c2bb0 5827 hold_lkb(lkb);
597d0cae
DT		 5828 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5829 spin_unlock(&ua->proc->locks_spin);
5830 out:
85e86edf 5831 dlm_unlock_recovery(ls);
597d0cae
DT		 5832 return error;
5833}
5834
5835int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
d7db923e
DT		 5836 int mode, uint32_t flags, uint32_t lkid, char *lvb_in,
5837 unsigned long timeout_cs)
597d0cae
DT		 5838{
5839 struct dlm_lkb *lkb;
5840 struct dlm_args args;
5841 struct dlm_user_args *ua;
5842 int error;
5843
85e86edf 5844 dlm_lock_recovery(ls);
597d0cae
DT		 5845
5846 error = find_lkb(ls, lkid, &lkb);
5847 if (error)
5848 goto out;
5849
5850 /* user can change the params on its lock when it converts it, or
5851 add an lvb that didn't exist before */
5852
d292c0cc 5853 ua = lkb->lkb_ua;
597d0cae
DT		 5854
5855 if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) {
573c24c4 5856 ua->lksb.sb_lvbptr = kzalloc(DLM_USER_LVB_LEN, GFP_NOFS);
597d0cae
DT		 5857 if (!ua->lksb.sb_lvbptr) {
5858 error = -ENOMEM;
5859 goto out_put;
5860 }
5861 }
5862 if (lvb_in && ua->lksb.sb_lvbptr)
5863 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
5864
d7db923e 5865 ua->xid = ua_tmp->xid;
597d0cae
DT		 5866 ua->castparam = ua_tmp->castparam;
5867 ua->castaddr = ua_tmp->castaddr;
5868 ua->bastparam = ua_tmp->bastparam;
5869 ua->bastaddr = ua_tmp->bastaddr;
10948eb4 5870 ua->user_lksb = ua_tmp->user_lksb;
597d0cae 5871
d7db923e 5872 error = set_lock_args(mode, &ua->lksb, flags, 0, timeout_cs,
e5dae548 5873 fake_astfn, ua, fake_bastfn, &args);
597d0cae
DT		 5874 if (error)
5875 goto out_put;
5876
5877 error = convert_lock(ls, lkb, &args);
5878
c85d65e9 5879 if (error == -EINPROGRESS || error == -EAGAIN || error == -EDEADLK)
597d0cae
DT		 5880 error = 0;
5881 out_put:
5882 dlm_put_lkb(lkb);
5883 out:
85e86edf 5884 dlm_unlock_recovery(ls);
597d0cae
DT		 5885 kfree(ua_tmp);
5886 return error;
5887}
5888
2ab4bd8e
DT		 5889/*
5890 * The caller asks for an orphan lock on a given resource with a given mode.
5891 * If a matching lock exists, it's moved to the owner's list of locks and
5892 * the lkid is returned.
5893 */
5894
5895int dlm_user_adopt_orphan(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5896 int mode, uint32_t flags, void *name, unsigned int namelen,
5897 unsigned long timeout_cs, uint32_t *lkid)
5898{
5899 struct dlm_lkb *lkb;
5900 struct dlm_user_args *ua;
5901 int found_other_mode = 0;
5902 int found = 0;
5903 int rv = 0;
5904
5905 mutex_lock(&ls->ls_orphans_mutex);
5906 list_for_each_entry(lkb, &ls->ls_orphans, lkb_ownqueue) {
5907 if (lkb->lkb_resource->res_length != namelen)
5908 continue;
5909 if (memcmp(lkb->lkb_resource->res_name, name, namelen))
5910 continue;
5911 if (lkb->lkb_grmode != mode) {
5912 found_other_mode = 1;
5913 continue;
5914 }
5915
5916 found = 1;
5917 list_del_init(&lkb->lkb_ownqueue);
5918 lkb->lkb_flags &= ~DLM_IFL_ORPHAN;
5919 *lkid = lkb->lkb_id;
5920 break;
5921 }
5922 mutex_unlock(&ls->ls_orphans_mutex);
5923
5924 if (!found && found_other_mode) {
5925 rv = -EAGAIN;
5926 goto out;
5927 }
5928
5929 if (!found) {
5930 rv = -ENOENT;
5931 goto out;
5932 }
5933
5934 lkb->lkb_exflags = flags;
5935 lkb->lkb_ownpid = (int) current->pid;
5936
5937 ua = lkb->lkb_ua;
5938
5939 ua->proc = ua_tmp->proc;
5940 ua->xid = ua_tmp->xid;
5941 ua->castparam = ua_tmp->castparam;
5942 ua->castaddr = ua_tmp->castaddr;
5943 ua->bastparam = ua_tmp->bastparam;
5944 ua->bastaddr = ua_tmp->bastaddr;
5945 ua->user_lksb = ua_tmp->user_lksb;
5946
5947 /*
5948 * The lkb reference from the ls_orphans list was not
5949 * removed above, and is now considered the reference
5950 * for the proc locks list.
5951 */
5952
5953 spin_lock(&ua->proc->locks_spin);
5954 list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks);
5955 spin_unlock(&ua->proc->locks_spin);
5956 out:
5957 kfree(ua_tmp);
5958 return rv;
5959}
5960
597d0cae
DT		 5961int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
5962 uint32_t flags, uint32_t lkid, char *lvb_in)
5963{
5964 struct dlm_lkb *lkb;
5965 struct dlm_args args;
5966 struct dlm_user_args *ua;
5967 int error;
5968
85e86edf 5969 dlm_lock_recovery(ls);
597d0cae
DT		 5970
5971 error = find_lkb(ls, lkid, &lkb);
5972 if (error)
5973 goto out;
5974
d292c0cc 5975 ua = lkb->lkb_ua;
597d0cae
DT		 5976
5977 if (lvb_in && ua->lksb.sb_lvbptr)
5978 memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN);
b434eda6
PC		 5979 if (ua_tmp->castparam)
5980 ua->castparam = ua_tmp->castparam;
cc346d55 5981 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 5982
5983 error = set_unlock_args(flags, ua, &args);
5984 if (error)
5985 goto out_put;
5986
5987 error = unlock_lock(ls, lkb, &args);
5988
5989 if (error == -DLM_EUNLOCK)
5990 error = 0;
ef0c2bb0
DT		 5991 /* from validate_unlock_args() */
5992 if (error == -EBUSY && (flags & DLM_LKF_FORCEUNLOCK))
5993 error = 0;
597d0cae
DT		 5994 if (error)
5995 goto out_put;
5996
5997 spin_lock(&ua->proc->locks_spin);
23e8e1aa 5998 /* dlm_user_add_cb() may have already taken lkb off the proc list */
a1bc86e6
DT		 5999 if (!list_empty(&lkb->lkb_ownqueue))
6000 list_move(&lkb->lkb_ownqueue, &ua->proc->unlocking);
597d0cae 6001 spin_unlock(&ua->proc->locks_spin);
597d0cae
DT		 6002 out_put:
6003 dlm_put_lkb(lkb);
6004 out:
85e86edf 6005 dlm_unlock_recovery(ls);
ef0c2bb0 6006 kfree(ua_tmp);
597d0cae
DT		 6007 return error;
6008}
6009
6010int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
6011 uint32_t flags, uint32_t lkid)
6012{
6013 struct dlm_lkb *lkb;
6014 struct dlm_args args;
6015 struct dlm_user_args *ua;
6016 int error;
6017
85e86edf 6018 dlm_lock_recovery(ls);
597d0cae
DT		 6019
6020 error = find_lkb(ls, lkid, &lkb);
6021 if (error)
6022 goto out;
6023
d292c0cc 6024 ua = lkb->lkb_ua;
b434eda6
PC		 6025 if (ua_tmp->castparam)
6026 ua->castparam = ua_tmp->castparam;
c059f70e 6027 ua->user_lksb = ua_tmp->user_lksb;
597d0cae
DT		 6028
6029 error = set_unlock_args(flags, ua, &args);
6030 if (error)
6031 goto out_put;
6032
6033 error = cancel_lock(ls, lkb, &args);
6034
6035 if (error == -DLM_ECANCEL)
6036 error = 0;
ef0c2bb0
DT		 6037 /* from validate_unlock_args() */
6038 if (error == -EBUSY)
6039 error = 0;
597d0cae
DT		 6040 out_put:
6041 dlm_put_lkb(lkb);
6042 out:
85e86edf 6043 dlm_unlock_recovery(ls);
ef0c2bb0 6044 kfree(ua_tmp);
597d0cae
DT		 6045 return error;
6046}
6047
8b4021fa
DT		 6048int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
6049{
6050 struct dlm_lkb *lkb;
6051 struct dlm_args args;
6052 struct dlm_user_args *ua;
6053 struct dlm_rsb *r;
6054 int error;
6055
6056 dlm_lock_recovery(ls);
6057
6058 error = find_lkb(ls, lkid, &lkb);
6059 if (error)
6060 goto out;
6061
d292c0cc 6062 ua = lkb->lkb_ua;
8b4021fa
DT		 6063
6064 error = set_unlock_args(flags, ua, &args);
6065 if (error)
6066 goto out_put;
6067
6068 /* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
6069
6070 r = lkb->lkb_resource;
6071 hold_rsb(r);
6072 lock_rsb(r);
6073
6074 error = validate_unlock_args(lkb, &args);
6075 if (error)
6076 goto out_r;
6077 lkb->lkb_flags |= DLM_IFL_DEADLOCK_CANCEL;
6078
6079 error = _cancel_lock(r, lkb);
6080 out_r:
6081 unlock_rsb(r);
6082 put_rsb(r);
6083
6084 if (error == -DLM_ECANCEL)
6085 error = 0;
6086 /* from validate_unlock_args() */
6087 if (error == -EBUSY)
6088 error = 0;
6089 out_put:
6090 dlm_put_lkb(lkb);
6091 out:
6092 dlm_unlock_recovery(ls);
6093 return error;
6094}
6095
ef0c2bb0
DT		 6096/* lkb's that are removed from the waiters list by revert are just left on the
6097 orphans list with the granted orphan locks, to be freed by purge */
6098
597d0cae
DT		 6099static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
6100{
ef0c2bb0
DT		 6101 struct dlm_args args;
6102 int error;
597d0cae 6103
2ab4bd8e 6104 hold_lkb(lkb); /* reference for the ls_orphans list */
ef0c2bb0
DT		 6105 mutex_lock(&ls->ls_orphans_mutex);
6106 list_add_tail(&lkb->lkb_ownqueue, &ls->ls_orphans);
6107 mutex_unlock(&ls->ls_orphans_mutex);
597d0cae 6108
d292c0cc 6109 set_unlock_args(0, lkb->lkb_ua, &args);
ef0c2bb0
DT		 6110
6111 error = cancel_lock(ls, lkb, &args);
6112 if (error == -DLM_ECANCEL)
6113 error = 0;
6114 return error;
597d0cae
DT		 6115}
6116
da8c6663
DT		 6117/* The FORCEUNLOCK flag allows the unlock to go ahead even if the lkb isn't
6118 granted. Regardless of what rsb queue the lock is on, it's removed and
6119 freed. The IVVALBLK flag causes the lvb on the resource to be invalidated
6120 if our lock is PW/EX (it's ignored if our granted mode is smaller.) */
597d0cae
DT		 6121
6122static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb)
6123{
597d0cae
DT		 6124 struct dlm_args args;
6125 int error;
6126
da8c6663
DT		 6127 set_unlock_args(DLM_LKF_FORCEUNLOCK | DLM_LKF_IVVALBLK,
6128 lkb->lkb_ua, &args);
597d0cae
DT		 6129
6130 error = unlock_lock(ls, lkb, &args);
6131 if (error == -DLM_EUNLOCK)
6132 error = 0;
6133 return error;
6134}
6135
ef0c2bb0
DT		 6136/* We have to release clear_proc_locks mutex before calling unlock_proc_lock()
6137 (which does lock_rsb) due to deadlock with receiving a message that does
23e8e1aa 6138 lock_rsb followed by dlm_user_add_cb() */
ef0c2bb0
DT		 6139
6140static struct dlm_lkb *del_proc_lock(struct dlm_ls *ls,
6141 struct dlm_user_proc *proc)
6142{
6143 struct dlm_lkb *lkb = NULL;
6144
6145 mutex_lock(&ls->ls_clear_proc_locks);
6146 if (list_empty(&proc->locks))
6147 goto out;
6148
6149 lkb = list_entry(proc->locks.next, struct dlm_lkb, lkb_ownqueue);
6150 list_del_init(&lkb->lkb_ownqueue);
6151
6152 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
6153 lkb->lkb_flags |= DLM_IFL_ORPHAN;
6154 else
6155 lkb->lkb_flags |= DLM_IFL_DEAD;
6156 out:
6157 mutex_unlock(&ls->ls_clear_proc_locks);
6158 return lkb;
6159}
6160
23e8e1aa 6161/* The ls_clear_proc_locks mutex protects against dlm_user_add_cb() which
597d0cae
DT		 6162 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts,
6163 which we clear here. */
6164
6165/* proc CLOSING flag is set so no more device_reads should look at proc->asts
6166 list, and no more device_writes should add lkb's to proc->locks list; so we
6167 shouldn't need to take asts_spin or locks_spin here. this assumes that
6168 device reads/writes/closes are serialized -- FIXME: we may need to serialize
6169 them ourself. */
6170
6171void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6172{
6173 struct dlm_lkb *lkb, *safe;
6174
85e86edf 6175 dlm_lock_recovery(ls);
597d0cae 6176
ef0c2bb0
DT		 6177 while (1) {
6178 lkb = del_proc_lock(ls, proc);
6179 if (!lkb)
6180 break;
84d8cd69 6181 del_timeout(lkb);
ef0c2bb0 6182 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT)
597d0cae 6183 orphan_proc_lock(ls, lkb);
ef0c2bb0 6184 else
597d0cae 6185 unlock_proc_lock(ls, lkb);
597d0cae
DT		 6186
6187 /* this removes the reference for the proc->locks list
6188 added by dlm_user_request, it may result in the lkb
6189 being freed */
6190
6191 dlm_put_lkb(lkb);
6192 }
a1bc86e6 6193
ef0c2bb0
DT		 6194 mutex_lock(&ls->ls_clear_proc_locks);
6195
a1bc86e6
DT		 6196 /* in-progress unlocks */
6197 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6198 list_del_init(&lkb->lkb_ownqueue);
6199 lkb->lkb_flags |= DLM_IFL_DEAD;
6200 dlm_put_lkb(lkb);
6201 }
6202
23e8e1aa 6203 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
8304d6f2
DT		 6204 memset(&lkb->lkb_callbacks, 0,
6205 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
23e8e1aa 6206 list_del_init(&lkb->lkb_cb_list);
a1bc86e6
DT		 6207 dlm_put_lkb(lkb);
6208 }
6209
597d0cae 6210 mutex_unlock(&ls->ls_clear_proc_locks);
85e86edf 6211 dlm_unlock_recovery(ls);
597d0cae 6212}
a1bc86e6 6213
8499137d
DT		 6214static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
6215{
6216 struct dlm_lkb *lkb, *safe;
6217
6218 while (1) {
6219 lkb = NULL;
6220 spin_lock(&proc->locks_spin);
6221 if (!list_empty(&proc->locks)) {
6222 lkb = list_entry(proc->locks.next, struct dlm_lkb,
6223 lkb_ownqueue);
6224 list_del_init(&lkb->lkb_ownqueue);
6225 }
6226 spin_unlock(&proc->locks_spin);
6227
6228 if (!lkb)
6229 break;
6230
6231 lkb->lkb_flags |= DLM_IFL_DEAD;
6232 unlock_proc_lock(ls, lkb);
6233 dlm_put_lkb(lkb); /* ref from proc->locks list */
6234 }
6235
6236 spin_lock(&proc->locks_spin);
6237 list_for_each_entry_safe(lkb, safe, &proc->unlocking, lkb_ownqueue) {
6238 list_del_init(&lkb->lkb_ownqueue);
6239 lkb->lkb_flags |= DLM_IFL_DEAD;
6240 dlm_put_lkb(lkb);
6241 }
6242 spin_unlock(&proc->locks_spin);
6243
6244 spin_lock(&proc->asts_spin);
23e8e1aa 6245 list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_cb_list) {
8304d6f2
DT		 6246 memset(&lkb->lkb_callbacks, 0,
6247 sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
23e8e1aa 6248 list_del_init(&lkb->lkb_cb_list);
8499137d
DT		 6249 dlm_put_lkb(lkb);
6250 }
6251 spin_unlock(&proc->asts_spin);
6252}
6253
6254/* pid of 0 means purge all orphans */
6255
6256static void do_purge(struct dlm_ls *ls, int nodeid, int pid)
6257{
6258 struct dlm_lkb *lkb, *safe;
6259
6260 mutex_lock(&ls->ls_orphans_mutex);
6261 list_for_each_entry_safe(lkb, safe, &ls->ls_orphans, lkb_ownqueue) {
6262 if (pid && lkb->lkb_ownpid != pid)
6263 continue;
6264 unlock_proc_lock(ls, lkb);
6265 list_del_init(&lkb->lkb_ownqueue);
6266 dlm_put_lkb(lkb);
6267 }
6268 mutex_unlock(&ls->ls_orphans_mutex);
6269}
6270
6271static int send_purge(struct dlm_ls *ls, int nodeid, int pid)
6272{
6273 struct dlm_message *ms;
6274 struct dlm_mhandle *mh;
6275 int error;
6276
6277 error = _create_message(ls, sizeof(struct dlm_message), nodeid,
6278 DLM_MSG_PURGE, &ms, &mh);
6279 if (error)
6280 return error;
6281 ms->m_nodeid = nodeid;
6282 ms->m_pid = pid;
6283
6284 return send_message(mh, ms);
6285}
6286
6287int dlm_user_purge(struct dlm_ls *ls, struct dlm_user_proc *proc,
6288 int nodeid, int pid)
6289{
6290 int error = 0;
6291
2ab4bd8e 6292 if (nodeid && (nodeid != dlm_our_nodeid())) {
8499137d
DT		 6293 error = send_purge(ls, nodeid, pid);
6294 } else {
85e86edf 6295 dlm_lock_recovery(ls);
8499137d
DT		 6296 if (pid == current->pid)
6297 purge_proc_locks(ls, proc);
6298 else
6299 do_purge(ls, nodeid, pid);
85e86edf 6300 dlm_unlock_recovery(ls);
8499137d
DT		 6301 }
6302 return error;
6303}
6304
Linux 6.x block layer and io_uring tree(s)